# Electronic Supplementary Material (ESI) for Physical Chemistry Chemical Physics # This journal is © The Owner Societies 2012 data_global _journal_name_full Phys.Chem.Chem.Phys.(PCCP) _journal_coden_cambridge 1326 _journal_year ? _journal_volume ? _journal_page_first ? _publ_contact_author_name 'Chick Wilson' _publ_author_name 'Chick Wilson' _publ_contact_author_email C.C.Wilson@bath.ac.uk data_dmuox_100k _database_code_depnum_ccdc_archive 'CCDC 894617' #TrackingRef 'NN-DMU_oxalic_100K_X-ray_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.26 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 14.992(2) _cell_length_b 6.4333(7) _cell_length_c 13.610(2) _cell_angle_alpha 90.00 _cell_angle_beta 107.306(12) _cell_angle_gamma 90.00 _cell_volume 1253.2(3) _cell_formula_units_Z 4 _cell_measurement_temperature 100 _cell_measurement_reflns_used 10680 _cell_measurement_theta_min 6.07 _cell_measurement_theta_max 55.03 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 0.4 _exptl_crystal_size_mid 0.2 _exptl_crystal_size_min 0.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.411 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 568 _exptl_absorpt_coefficient_mu 0.120 _exptl_absorpt_correction_type multi-scan _exptl_absorpt_correction_T_min 0.8209 _exptl_absorpt_correction_T_max 1.0000 _exptl_absorpt_process_details 'ABSCOR, Rigaku 1995' _exptl_special_details ; ? ; _diffrn_ambient_temperature 100 _diffrn_radiation_wavelength 0.71075 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'Rigaku R-AXIS RAPID IP Image Plate' _diffrn_measurement_method 'Image plate' _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 14722 _diffrn_reflns_av_R_equivalents 0.0213 _diffrn_reflns_av_sigmaI/netI 0.0212 _diffrn_reflns_limit_h_min -19 _diffrn_reflns_limit_h_max 19 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_k_max 8 _diffrn_reflns_limit_l_min -17 _diffrn_reflns_limit_l_max 17 _diffrn_reflns_theta_min 3.03 _diffrn_reflns_theta_max 27.48 _reflns_number_total 2753 _reflns_number_gt 2097 _reflns_threshold_expression >2\s(I) _computing_data_collection 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_cell_refinement 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_data_reduction 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_structure_solution 'SHELXS-97 (Sheldrick, 2008)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0687P)^2^+0.1788P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difamp _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 2753 _refine_ls_number_parameters 235 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0566 _refine_ls_R_factor_gt 0.0443 _refine_ls_wR_factor_ref 0.1180 _refine_ls_wR_factor_gt 0.1111 _refine_ls_goodness_of_fit_ref 1.077 _refine_ls_restrained_S_all 1.077 _refine_ls_shift/su_max 0.002 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.48080(7) 0.23914(15) 0.37132(8) 0.0269(3) Uani 1 1 d . . . N1 N 0.56703(9) -0.0589(2) 0.39715(10) 0.0241(3) Uani 1 1 d . . . N2 N 0.40500(8) -0.06629(19) 0.34393(10) 0.0240(3) Uani 1 1 d . . . C14 C 0.48534(10) 0.0396(2) 0.37111(10) 0.0214(3) Uani 1 1 d . . . C17 C 0.40442(12) -0.2926(2) 0.34167(14) 0.0286(3) Uani 1 1 d . . . C18 C 0.31603(11) 0.0451(3) 0.31512(15) 0.0316(4) Uani 1 1 d . . . O2 O 0.98321(7) 0.75111(15) 0.60451(8) 0.0248(3) Uani 1 1 d . . . N3 N 1.05724(8) 1.05468(19) 0.65519(9) 0.0231(3) Uani 1 1 d . . . N4 N 0.89767(9) 1.0495(2) 0.57324(10) 0.0236(3) Uani 1 1 d . . . C2 C 0.97897(10) 0.9489(2) 0.61005(10) 0.0204(3) Uani 1 1 d . . . C5 C 1.05707(11) 1.2809(2) 0.66369(13) 0.0267(3) Uani 1 1 d . . . C6 C 1.14635(11) 0.9461(3) 0.69471(13) 0.0277(3) Uani 1 1 d . . . O3 O 0.61303(7) 0.47901(16) 0.41178(8) 0.0264(3) Uani 1 1 d . . . O4 O 0.71833(8) 0.22795(16) 0.46794(11) 0.0405(3) Uani 1 1 d . . . O5 O 0.85156(7) 0.51271(16) 0.54501(8) 0.0273(3) Uani 1 1 d . . . O6 O 0.75460(8) 0.75993(16) 0.45950(9) 0.0314(3) Uani 1 1 d . . . C8 C 0.77198(10) 0.5805(2) 0.48746(11) 0.0218(3) Uani 1 1 d . . . C10 C 0.69567(10) 0.4098(2) 0.45340(11) 0.0232(3) Uani 1 1 d . . . H12 H 0.8957(13) 1.187(3) 0.5694(14) 0.034(5) Uiso 1 1 d . . . H2 H 0.6198(14) 0.019(3) 0.4180(14) 0.039(5) Uiso 1 1 d . . . H16 H 1.1958(14) 1.011(3) 0.6711(15) 0.046(5) Uiso 1 1 d . . . H3 H 0.4317(14) -0.347(3) 0.2904(15) 0.046(5) Uiso 1 1 d . . . H11 H 0.8471(14) 0.970(3) 0.5362(14) 0.039(5) Uiso 1 1 d . . . H1 H 0.5686(14) -0.200(3) 0.3967(14) 0.039(5) Uiso 1 1 d . . . H13 H 1.0067(13) 1.327(3) 0.6902(13) 0.034(5) Uiso 1 1 d . . . H6 H 0.317(2) 0.151(5) 0.274(3) 0.126(13) Uiso 1 1 d . . . H4 H 0.4382(14) -0.350(3) 0.4063(15) 0.043(5) Uiso 1 1 d . . . H15 H 1.0524(14) 1.343(3) 0.5990(15) 0.043(5) Uiso 1 1 d . . . H14 H 1.1162(16) 1.326(3) 0.7114(16) 0.053(6) Uiso 1 1 d . . . H7 H 0.293(2) 0.068(5) 0.369(3) 0.126(12) Uiso 1 1 d . . . H8 H 0.268(2) -0.045(5) 0.271(3) 0.111(11) Uiso 1 1 d . . . H18 H 1.1665(15) 0.953(3) 0.7698(18) 0.065(7) Uiso 1 1 d . . . H5 H 0.3402(18) -0.344(3) 0.3223(18) 0.065(7) Uiso 1 1 d . . . H17 H 1.1369(19) 0.807(4) 0.671(2) 0.075(8) Uiso 1 1 d . . . H9 H 0.5490(18) 0.343(4) 0.3915(19) 0.079(8) Uiso 1 1 d . . . H10 H 0.9084(18) 0.645(4) 0.5689(18) 0.073(7) Uiso 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0210(5) 0.0172(5) 0.0400(6) 0.0016(4) 0.0051(5) 0.0005(4) N1 0.0185(6) 0.0172(7) 0.0336(7) 0.0007(5) 0.0033(5) -0.0008(5) N2 0.0174(6) 0.0198(6) 0.0319(6) 0.0009(5) 0.0026(5) 0.0008(5) C14 0.0217(7) 0.0200(7) 0.0218(7) 0.0022(5) 0.0053(6) 0.0010(6) C17 0.0249(8) 0.0203(8) 0.0384(9) -0.0015(7) 0.0062(7) -0.0029(6) C18 0.0179(8) 0.0285(9) 0.0445(10) 0.0005(8) 0.0035(7) 0.0028(7) O2 0.0213(5) 0.0175(5) 0.0331(5) -0.0009(4) 0.0043(4) -0.0003(4) N3 0.0183(6) 0.0192(6) 0.0294(6) -0.0005(5) 0.0036(5) -0.0003(5) N4 0.0208(7) 0.0160(7) 0.0315(7) -0.0007(5) 0.0040(6) -0.0011(5) C2 0.0208(7) 0.0192(7) 0.0214(6) 0.0010(5) 0.0064(6) -0.0002(6) C5 0.0249(8) 0.0209(8) 0.0336(8) -0.0047(6) 0.0074(7) -0.0045(6) C6 0.0185(8) 0.0266(8) 0.0342(8) 0.0008(7) 0.0021(7) 0.0001(6) O3 0.0183(5) 0.0188(5) 0.0385(6) 0.0029(4) 0.0029(5) 0.0000(4) O4 0.0221(6) 0.0160(6) 0.0759(9) 0.0008(5) 0.0029(6) -0.0003(5) O5 0.0206(6) 0.0195(6) 0.0369(6) 0.0036(4) 0.0009(5) -0.0004(4) O6 0.0232(6) 0.0179(6) 0.0468(7) 0.0037(5) 0.0008(5) -0.0016(4) C8 0.0202(7) 0.0186(7) 0.0269(7) 0.0009(6) 0.0076(6) 0.0010(6) C10 0.0225(8) 0.0184(7) 0.0295(7) -0.0006(6) 0.0087(6) -0.0011(6) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C14 1.2857(17) . ? O1 H9 1.19(3) . ? N1 C14 1.3299(18) . ? N1 H2 0.91(2) . ? N1 H1 0.91(2) . ? N2 C14 1.3365(19) . ? N2 C17 1.4563(19) . ? N2 C18 1.461(2) . ? C17 H3 0.97(2) . ? C17 H4 0.95(2) . ? C17 H5 0.98(2) . ? C18 H6 0.88(4) . ? C18 H7 0.92(4) . ? C18 H8 0.98(3) . ? O2 C2 1.2777(16) . ? O2 H10 1.28(3) . ? N3 C2 1.3372(19) . ? N3 C5 1.4601(19) . ? N3 C6 1.461(2) . ? N4 C2 1.3385(19) . ? N4 H12 0.89(2) . ? N4 H11 0.93(2) . ? C5 H13 0.975(18) . ? C5 H15 0.95(2) . ? C5 H14 0.98(2) . ? C6 H16 0.98(2) . ? C6 H18 0.98(2) . ? C6 H17 0.95(3) . ? O3 C10 1.2793(18) . ? O3 H9 1.26(3) . ? O4 C10 1.2178(17) . ? O5 C8 1.2927(18) . ? O5 H10 1.18(3) . ? O6 C8 1.2191(17) . ? C8 C10 1.554(2) . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C14 O1 H9 121.6(12) . . ? C14 N1 H2 117.8(12) . . ? C14 N1 H1 119.9(13) . . ? H2 N1 H1 122.3(18) . . ? C14 N2 C17 120.97(12) . . ? C14 N2 C18 119.98(13) . . ? C17 N2 C18 119.05(13) . . ? O1 C14 N1 121.34(13) . . ? O1 C14 N2 117.75(12) . . ? N1 C14 N2 120.91(13) . . ? N2 C17 H3 112.0(11) . . ? N2 C17 H4 111.6(12) . . ? H3 C17 H4 107.7(16) . . ? N2 C17 H5 110.2(13) . . ? H3 C17 H5 105.9(18) . . ? H4 C17 H5 109.2(17) . . ? N2 C18 H6 111(2) . . ? N2 C18 H7 113(2) . . ? H6 C18 H7 118(3) . . ? N2 C18 H8 108.6(18) . . ? H6 C18 H8 103(3) . . ? H7 C18 H8 102(2) . . ? C2 O2 H10 120.1(11) . . ? C2 N3 C5 121.43(12) . . ? C2 N3 C6 120.49(13) . . ? C5 N3 C6 118.05(12) . . ? C2 N4 H12 121.0(12) . . ? C2 N4 H11 116.1(12) . . ? H12 N4 H11 120.8(17) . . ? O2 C2 N3 118.79(13) . . ? O2 C2 N4 120.99(13) . . ? N3 C2 N4 120.21(13) . . ? N3 C5 H13 110.6(10) . . ? N3 C5 H15 110.3(12) . . ? H13 C5 H15 111.3(16) . . ? N3 C5 H14 109.2(12) . . ? H13 C5 H14 108.3(16) . . ? H15 C5 H14 107.0(16) . . ? N3 C6 H16 111.9(11) . . ? N3 C6 H18 109.2(13) . . ? H16 C6 H18 107.2(17) . . ? N3 C6 H17 107.4(16) . . ? H16 C6 H17 109.9(19) . . ? H18 C6 H17 111.2(19) . . ? C10 O3 H9 115.4(12) . . ? C8 O5 H10 112.7(12) . . ? O6 C8 O5 125.56(13) . . ? O6 C8 C10 120.40(13) . . ? O5 C8 C10 114.03(12) . . ? O4 C10 O3 126.37(13) . . ? O4 C10 C8 119.04(13) . . ? O3 C10 C8 114.59(12) . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag C17 N2 C14 O1 179.90(13) . . . . ? C18 N2 C14 O1 0.4(2) . . . . ? C17 N2 C14 N1 -0.2(2) . . . . ? C18 N2 C14 N1 -179.69(14) . . . . ? C5 N3 C2 O2 179.83(12) . . . . ? C6 N3 C2 O2 1.76(19) . . . . ? C5 N3 C2 N4 -1.4(2) . . . . ? C6 N3 C2 N4 -179.45(13) . . . . ? O6 C8 C10 O4 168.17(15) . . . . ? O5 C8 C10 O4 -11.40(19) . . . . ? O6 C8 C10 O3 -11.90(19) . . . . ? O5 C8 C10 O3 168.54(12) . . . . ? N1 O1 O3 O4 -8.61(6) . . . . ? N4 O2 O5 O6 17.16(6) . . . . ? _diffrn_measured_fraction_theta_max 0.957 _diffrn_reflns_theta_full 27.48 _diffrn_measured_fraction_theta_full 0.957 _refine_diff_density_max 0.312 _refine_diff_density_min -0.201 _refine_diff_density_rms 0.053 # Attachment 'NN-DMU_oxalic_150K_neutron_CIF.cif' data_dmuox_150 _database_code_depnum_ccdc_archive 'CCDC 894618' #TrackingRef 'NN-DMU_oxalic_150K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioc acid ; _chemical_name_common ; bis(N,N-Dimethylurea) & oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.740(5) _cell_length_b 6.440(5) _cell_length_c 13.540(5) _cell_angle_alpha 90.00 _cell_angle_beta 110.880(10) _cell_angle_gamma 90.00 _cell_volume 630.6(7) _cell_formula_units_Z 2 _cell_measurement_temperature 150 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.401 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 150 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_reflns_number 7056 _diffrn_reflns_av_R_equivalents 0.1952 _diffrn_reflns_av_sigmaI/netI 0.1137 _diffrn_reflns_limit_h_min -11 _diffrn_reflns_limit_h_max 11 _diffrn_reflns_limit_k_min -9 _diffrn_reflns_limit_k_max 9 _diffrn_reflns_limit_l_min -16 _diffrn_reflns_limit_l_max 17 _reflns_number_total 1449 _reflns_number_gt 925 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.74 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 0.1(2) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 1449 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.1310 _refine_ls_R_factor_gt 0.0706 _refine_ls_wR_factor_ref 0.1224 _refine_ls_wR_factor_gt 0.1146 _refine_ls_goodness_of_fit_ref 1.532 _refine_ls_restrained_S_all 1.532 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.4993(3) 0.2547(3) 0.3813(3) 0.0342(7) Uani 1 1 d . . . O3 O 0.7598(3) 0.0165(3) 0.4358(3) 0.0328(7) Uani 1 1 d . . . O4 O 0.9666(4) 0.2655(3) 0.5028(3) 0.0552(11) Uani 1 1 d . . . N1 N 0.34701(17) 0.5579(2) 0.33980(14) 0.0313(4) Uani 1 1 d . . . N2 N 0.66721(18) 0.55401(18) 0.41245(14) 0.0313(4) Uani 1 1 d . . . C1 C 0.5060(2) 0.4533(2) 0.37825(19) 0.0259(5) Uani 1 1 d . . . C2 C 0.3427(3) 0.7833(3) 0.3346(2) 0.0382(7) Uani 1 1 d . . . H3 H 0.3815(17) 0.8531(10) 0.4080(7) 0.108(3) Uani 1 1 d . . . H4 H 0.2158(10) 0.8331(10) 0.2854(10) 0.151(5) Uani 1 1 d . . . H5 H 0.4428(11) 0.8429(8) 0.3024(6) 0.082(2) Uani 1 1 d . . . C3 C 0.1708(3) 0.4463(3) 0.3056(3) 0.0395(7) Uani 1 1 d . . . H6 H 0.1127(17) 0.449(3) 0.2316(8) 0.192(9) Uani 1 1 d . . . H7 H 0.0875(14) 0.5029(16) 0.3396(11) 0.136(5) Uani 1 1 d . . . H8 H 0.1864(10) 0.3003(11) 0.3299(14) 0.178(8) Uani 1 1 d . . . C4 C 0.9244(2) 0.0853(2) 0.48380(18) 0.0280(5) Uani 1 1 d . . . H2 H 0.7850(6) 0.4697(6) 0.4457(5) 0.0495(15) Uani 1 1 d . . . H1 H 0.6792(6) 0.7097(6) 0.4171(4) 0.0454(12) Uani 1 1 d . . . H9 H 0.6404(6) 0.1488(6) 0.4118(4) 0.0468(12) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0238(10) 0.0152(8) 0.058(2) -0.0012(9) 0.0076(11) -0.0011(6) O3 0.0200(11) 0.0154(8) 0.055(2) -0.0049(9) 0.0037(11) 0.0008(6) O4 0.0237(9) 0.0153(9) 0.107(3) -0.0068(12) -0.0006(13) 0.0015(7) N1 0.0169(6) 0.0208(5) 0.0492(11) 0.0007(6) 0.0032(6) 0.0015(4) N2 0.0189(6) 0.0181(5) 0.0500(11) -0.0024(6) 0.0038(6) 0.0002(4) C1 0.0179(8) 0.0162(6) 0.0382(14) -0.0017(8) 0.0033(8) 0.0011(5) C2 0.0272(10) 0.0210(8) 0.061(2) 0.0045(10) 0.0094(11) 0.0047(7) H3 0.217(10) 0.037(3) 0.095(8) -0.006(3) 0.085(7) 0.001(4) H4 0.058(4) 0.038(3) 0.278(13) 0.030(5) -0.039(5) 0.010(2) H5 0.105(5) 0.037(2) 0.116(7) 0.016(3) 0.053(5) -0.005(3) C3 0.0197(10) 0.0295(10) 0.062(2) 0.0008(11) 0.0050(12) -0.0039(7) H6 0.126(9) 0.39(2) 0.040(7) 0.002(8) 0.005(5) -0.179(12) H7 0.071(6) 0.178(11) 0.182(12) -0.097(9) 0.072(7) -0.059(6) H8 0.054(4) 0.049(3) 0.37(2) 0.032(7) -0.005(7) -0.015(3) C4 0.0193(8) 0.0146(7) 0.0468(15) -0.0005(8) 0.0079(8) 0.0014(6) H2 0.0189(19) 0.0348(18) 0.082(4) -0.002(2) 0.003(2) 0.0063(12) H1 0.0345(18) 0.0266(16) 0.068(4) -0.0038(18) 0.010(2) -0.0007(13) H9 0.044(2) 0.0308(16) 0.060(4) -0.0070(19) 0.012(2) -0.0094(15) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.281(2) . ? O3 C4 1.285(3) . ? O4 C4 1.208(3) . ? N1 C1 1.335(2) . ? N1 C2 1.453(3) . ? N1 C3 1.463(3) . ? N2 C1 1.334(2) . ? C4 C4 1.550(3) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 121.67(14) . . ? C1 N1 C3 120.08(15) . . ? C2 N1 C3 118.20(15) . . ? O1 C1 N2 121.20(16) . . ? O1 C1 N1 118.27(16) . . ? N2 C1 N1 120.53(14) . . ? O4 C4 O3 125.7(2) . . ? O4 C4 C4 120.1(2) . 3_756 ? O3 C4 C4 114.22(19) . 3_756 ? loop_ _geom_hbond_atom_site_label_D _geom_hbond_atom_site_label_H _geom_hbond_atom_site_label_A _geom_hbond_distance_DH _geom_hbond_distance_HA _geom_hbond_distance_DA _geom_hbond_angle_DHA _geom_hbond_site_symmetry_A O3 H9 O1 1.213(5) 1.228(5) 2.430(3) 169.1(4) . _refine_diff_density_max 0.082 _refine_diff_density_min -0.110 _refine_diff_density_rms 0.016 # Attachment 'NN-DMU_oxalic_175K_neutron_CIF.cif' data_dmuox_175 _database_code_depnum_ccdc_archive 'CCDC 894619' #TrackingRef 'NN-DMU_oxalic_175K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.770(5) _cell_length_b 6.440(5) _cell_length_c 13.600(5) _cell_angle_alpha 90.00 _cell_angle_beta 111.140(10) _cell_angle_gamma 90.00 _cell_volume 634.7(7) _cell_formula_units_Z 2 _cell_measurement_temperature 175 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.392 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 175 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_reflns_number 6421 _diffrn_reflns_av_R_equivalents 0.1637 _diffrn_reflns_av_sigmaI/netI 0.0985 _diffrn_reflns_limit_h_min -11 _diffrn_reflns_limit_h_max 11 _diffrn_reflns_limit_k_min -9 _diffrn_reflns_limit_k_max 9 _diffrn_reflns_limit_l_min -15 _diffrn_reflns_limit_l_max 16 _reflns_number_total 1435 _reflns_number_gt 919 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.74 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 1.0(4) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 1435 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.1244 _refine_ls_R_factor_gt 0.0684 _refine_ls_wR_factor_ref 0.1231 _refine_ls_wR_factor_gt 0.1162 _refine_ls_goodness_of_fit_ref 1.681 _refine_ls_restrained_S_all 1.681 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.5002(3) 0.2552(3) 0.3807(2) 0.0374(7) Uani 1 1 d . . . O3 O 0.7599(3) 0.0165(3) 0.4367(3) 0.0378(7) Uani 1 1 d . . . O4 O 0.9671(4) 0.2652(3) 0.5014(3) 0.0618(12) Uani 1 1 d . . . N1 N 0.34711(18) 0.5576(2) 0.33990(13) 0.0347(4) Uani 1 1 d . . . N2 N 0.66714(17) 0.55395(19) 0.41247(13) 0.0345(4) Uani 1 1 d . . . C1 C 0.5065(2) 0.4537(2) 0.37850(17) 0.0275(4) Uani 1 1 d . . . C2 C 0.3420(3) 0.7827(3) 0.3351(2) 0.0419(7) Uani 1 1 d . . . H3 H 0.3833(18) 0.8514(10) 0.4079(8) 0.123(4) Uani 1 1 d . . . H4 H 0.2135(11) 0.8321(10) 0.2886(12) 0.182(6) Uani 1 1 d . . . H5 H 0.4373(12) 0.8416(9) 0.3021(7) 0.094(2) Uani 1 1 d . . . C3 C 0.1716(3) 0.4446(4) 0.3048(3) 0.0439(7) Uani 1 1 d . . . H6 H 0.1145(17) 0.447(3) 0.2337(8) 0.205(9) Uani 1 1 d . . . H7 H 0.0895(13) 0.5025(15) 0.3409(11) 0.137(5) Uani 1 1 d . . . H8 H 0.1855(11) 0.3038(15) 0.3319(13) 0.179(7) Uani 1 1 d . . . C4 C 0.9249(2) 0.0853(2) 0.48320(18) 0.0309(5) Uani 1 1 d . . . H2 H 0.7849(6) 0.4691(6) 0.4447(5) 0.0517(14) Uani 1 1 d . . . H1 H 0.6792(6) 0.7093(6) 0.4170(4) 0.0481(11) Uani 1 1 d . . . H9 H 0.6407(6) 0.1488(6) 0.4106(4) 0.0509(12) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0254(10) 0.0178(9) 0.0619(19) -0.0030(9) 0.0071(10) -0.0011(6) O3 0.0228(11) 0.0187(9) 0.065(2) -0.0050(9) 0.0079(11) 0.0002(6) O4 0.0245(10) 0.0192(9) 0.122(3) -0.0037(12) 0.0028(13) 0.0018(7) N1 0.0199(6) 0.0245(6) 0.0523(11) 0.0025(6) 0.0040(6) 0.0023(4) N2 0.0207(6) 0.0227(6) 0.0528(11) -0.0024(6) 0.0044(6) 0.0002(5) C1 0.0207(8) 0.0187(7) 0.0391(13) -0.0005(8) 0.0061(8) 0.0014(6) C2 0.0330(10) 0.0262(10) 0.061(2) 0.0041(10) 0.0105(11) 0.0071(7) H3 0.266(12) 0.040(3) 0.095(7) -0.009(3) 0.103(7) -0.010(5) H4 0.065(4) 0.041(3) 0.339(16) 0.041(6) -0.048(6) 0.006(3) H5 0.128(6) 0.041(2) 0.129(7) 0.017(3) 0.067(6) -0.004(3) C3 0.0219(11) 0.0380(12) 0.066(2) 0.0004(12) 0.0084(12) -0.0044(8) H6 0.131(9) 0.41(2) 0.041(6) 0.014(8) -0.003(6) -0.191(12) H7 0.070(6) 0.157(10) 0.202(13) -0.081(8) 0.069(7) -0.046(5) H8 0.061(5) 0.074(4) 0.330(19) 0.053(8) -0.016(7) -0.025(4) C4 0.0213(8) 0.0167(7) 0.0506(14) -0.0003(8) 0.0078(8) 0.0012(6) H2 0.0253(19) 0.0375(18) 0.079(4) -0.005(2) 0.003(2) 0.0047(13) H1 0.040(2) 0.0303(16) 0.070(3) -0.0023(18) 0.015(2) -0.0015(14) H9 0.044(2) 0.0371(18) 0.070(4) -0.007(2) 0.019(2) -0.0113(16) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.280(3) . ? O3 C4 1.286(3) . ? O4 C4 1.205(3) . ? N1 C1 1.337(2) . ? N1 C2 1.451(3) . ? N1 C3 1.465(3) . ? N2 C1 1.331(2) . ? C4 C4 1.547(3) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 121.61(15) . . ? C1 N1 C3 120.04(16) . . ? C2 N1 C3 118.31(16) . . ? O1 C1 N2 121.03(16) . . ? O1 C1 N1 118.10(16) . . ? N2 C1 N1 120.86(15) . . ? O4 C4 O3 125.5(2) . . ? O4 C4 C4 120.1(2) . 3_756 ? O3 C4 C4 114.38(19) . 3_756 ? _refine_diff_density_max 0.081 _refine_diff_density_min -0.102 _refine_diff_density_rms 0.015 # Attachment 'NN-DMU_oxalic_200K_X-ray_CIF.cif' data_dmuox_200k _database_code_depnum_ccdc_archive 'CCDC 894620' #TrackingRef 'NN-DMU_oxalic_200K_X-ray_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.26 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.7944(3) _cell_length_b 6.4482(2) _cell_length_c 13.6550(6) _cell_angle_alpha 90.00 _cell_angle_beta 111.407(2) _cell_angle_gamma 90.00 _cell_volume 638.95(4) _cell_formula_units_Z 2 _cell_measurement_temperature 200 _cell_measurement_reflns_used 5667 _cell_measurement_theta_min 6.32 _cell_measurement_theta_max 55.14 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 0.4 _exptl_crystal_size_mid 0.2 _exptl_crystal_size_min 0.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.384 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 284 _exptl_absorpt_coefficient_mu 0.118 _exptl_absorpt_correction_type multi-scan _exptl_absorpt_correction_T_min 0.7875 _exptl_absorpt_correction_T_max 1.0000 _exptl_absorpt_process_details 'ABSCOR, Rigaku 1995' _exptl_special_details ; ? ; _diffrn_ambient_temperature 200 _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'Rigaku R-AXIS RAPID IP Image Plate' _diffrn_measurement_method 'Image plate' _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 8005 _diffrn_reflns_av_R_equivalents 0.0165 _diffrn_reflns_av_sigmaI/netI 0.0135 _diffrn_reflns_limit_h_min -10 _diffrn_reflns_limit_h_max 10 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_k_max 8 _diffrn_reflns_limit_l_min -17 _diffrn_reflns_limit_l_max 17 _diffrn_reflns_theta_min 3.20 _diffrn_reflns_theta_max 27.48 _reflns_number_total 1460 _reflns_number_gt 1183 _reflns_threshold_expression >2\s(I) _computing_data_collection 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_cell_refinement 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_data_reduction 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_structure_solution 'SHELXS-97 (Sheldrick, 2008)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0856P)^2^+0.1542P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 1460 _refine_ls_number_parameters 94 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0577 _refine_ls_R_factor_gt 0.0511 _refine_ls_wR_factor_ref 0.1566 _refine_ls_wR_factor_gt 0.1498 _refine_ls_goodness_of_fit_ref 1.124 _refine_ls_restrained_S_all 1.124 _refine_ls_shift/su_max 0.014 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.50024(15) 0.25490(16) 0.38036(10) 0.0455(4) Uani 1 1 d . . . O3 O 0.76059(14) 0.01660(17) 0.43701(10) 0.0472(4) Uani 1 1 d . . . O4 O 0.96725(18) 0.26492(18) 0.50109(16) 0.0763(6) Uani 1 1 d . . . N1 N 0.34790(17) 0.5565(2) 0.34028(11) 0.0409(4) Uani 1 1 d . . . N2 N 0.66655(18) 0.5534(2) 0.41207(11) 0.0412(4) Uani 1 1 d . . . C1 C 0.50642(19) 0.4529(2) 0.37828(11) 0.0351(4) Uani 1 1 d . . . C2 C 0.3420(2) 0.7816(3) 0.33504(15) 0.0492(5) Uani 1 1 d . . . H2A H 0.3848 0.8376 0.4050 0.074 Uiso 1 1 calc R . . H2B H 0.2177 0.8263 0.2976 0.074 Uiso 1 1 calc R . . H2C H 0.4196 0.8297 0.2990 0.074 Uiso 1 1 calc R . . C3 C 0.1733(2) 0.4440(3) 0.30555(16) 0.0512(5) Uani 1 1 d . . . H3A H 0.1334 0.4182 0.2313 0.077 Uiso 1 1 calc R . . H3B H 0.0822 0.5254 0.3200 0.077 Uiso 1 1 calc R . . H3C H 0.1895 0.3144 0.3424 0.077 Uiso 1 1 calc R . . C4 C 0.92448(19) 0.0853(2) 0.48278(13) 0.0385(4) Uani 1 1 d . . . H2 H 0.762(3) 0.478(3) 0.4341(15) 0.046 Uiso 1 1 d . . . H1 H 0.671(3) 0.690(3) 0.4130(15) 0.046 Uiso 1 1 d . . . H9 H 0.642(4) 0.143(4) 0.413(2) 0.091(8) Uiso 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0318(6) 0.0272(6) 0.0714(8) -0.0006(5) 0.0115(5) 0.0000(4) O3 0.0294(6) 0.0282(6) 0.0755(8) -0.0040(5) 0.0090(5) 0.0010(4) O4 0.0315(7) 0.0257(6) 0.1496(16) -0.0038(7) 0.0069(8) 0.0010(5) N1 0.0273(7) 0.0319(7) 0.0576(8) 0.0009(5) 0.0084(6) 0.0011(5) N2 0.0286(7) 0.0279(7) 0.0608(8) -0.0012(6) 0.0090(6) 0.0006(5) C1 0.0306(7) 0.0298(7) 0.0428(8) -0.0007(5) 0.0107(6) 0.0011(5) C2 0.0403(9) 0.0341(9) 0.0695(11) 0.0062(7) 0.0156(8) 0.0079(6) C3 0.0282(8) 0.0461(9) 0.0705(11) 0.0006(8) 0.0078(7) -0.0020(7) C4 0.0306(8) 0.0266(7) 0.0567(9) -0.0008(6) 0.0139(6) 0.0004(6) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.2785(18) . ? O3 C4 1.2790(18) . ? O4 C4 1.2061(18) . ? N1 C1 1.3319(19) . ? N1 C2 1.453(2) . ? N1 C3 1.460(2) . ? N2 C1 1.3303(19) . ? C4 C4 1.553(3) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 121.89(13) . . ? C1 N1 C3 119.97(14) . . ? C2 N1 C3 118.12(13) . . ? O1 C1 N2 121.11(13) . . ? O1 C1 N1 118.19(13) . . ? N2 C1 N1 120.70(14) . . ? O4 C4 O3 125.81(14) . . ? O4 C4 C4 119.71(16) . 3_756 ? O3 C4 C4 114.47(15) . 3_756 ? _diffrn_measured_fraction_theta_max 0.997 _diffrn_reflns_theta_full 27.48 _diffrn_measured_fraction_theta_full 0.997 _refine_diff_density_max 0.265 _refine_diff_density_min -0.216 _refine_diff_density_rms 0.061 # Attachment 'NN-DMU_oxalic_200K_neutron_CIF.cif' data_dmuox_200 _database_code_depnum_ccdc_archive 'CCDC 894621' #TrackingRef 'NN-DMU_oxalic_200K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.790(5) _cell_length_b 6.450(5) _cell_length_c 13.660(5) _cell_angle_alpha 90.00 _cell_angle_beta 111.410(10) _cell_angle_gamma 90.00 _cell_volume 639.0(7) _cell_formula_units_Z 2 _cell_measurement_temperature 200 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.383 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 200 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 6073 _diffrn_reflns_av_R_equivalents 0.1633 _diffrn_reflns_av_sigmaI/netI 0.0975 _diffrn_reflns_limit_h_min -11 _diffrn_reflns_limit_h_max 11 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_k_max 9 _diffrn_reflns_limit_l_min -15 _diffrn_reflns_limit_l_max 17 _reflns_number_total 1341 _reflns_number_gt 832 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.71 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 2.4(5) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 1341 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.1303 _refine_ls_R_factor_gt 0.0672 _refine_ls_wR_factor_ref 0.1234 _refine_ls_wR_factor_gt 0.1145 _refine_ls_goodness_of_fit_ref 1.668 _refine_ls_restrained_S_all 1.668 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.5008(3) 0.2551(3) 0.3802(3) 0.0431(8) Uani 1 1 d . . . O3 O 0.7602(3) 0.0162(3) 0.4372(3) 0.0438(8) Uani 1 1 d . . . O4 O 0.9676(4) 0.2654(4) 0.5007(3) 0.0719(15) Uani 1 1 d . . . N1 N 0.34768(19) 0.5567(2) 0.34003(15) 0.0396(5) Uani 1 1 d . . . N2 N 0.66678(19) 0.5539(2) 0.41237(15) 0.0395(5) Uani 1 1 d . . . C1 C 0.5066(2) 0.4529(3) 0.37821(19) 0.0314(5) Uani 1 1 d . . . C2 C 0.3411(3) 0.7818(4) 0.3351(3) 0.0480(8) Uani 1 1 d . . . H3 H 0.3874(19) 0.8501(12) 0.4081(8) 0.129(4) Uani 1 1 d . . . H4 H 0.2133(12) 0.8321(12) 0.2910(13) 0.186(7) Uani 1 1 d . . . H5 H 0.4343(14) 0.8421(10) 0.3034(8) 0.105(3) Uani 1 1 d . . . C3 C 0.1721(4) 0.4440(4) 0.3051(3) 0.0489(7) Uani 1 1 d . . . H6 H 0.1048(18) 0.460(3) 0.2334(9) 0.209(10) Uani 1 1 d . . . H7 H 0.0951(14) 0.489(2) 0.3425(12) 0.153(6) Uani 1 1 d . . . H8 H 0.1888(12) 0.2996(16) 0.3239(18) 0.223(11) Uani 1 1 d . . . C4 C 0.9246(3) 0.0853(3) 0.4828(2) 0.0364(6) Uani 1 1 d . . . H2 H 0.7852(6) 0.4705(7) 0.4438(5) 0.0551(15) Uani 1 1 d . . . H1 H 0.6790(6) 0.7091(7) 0.4173(4) 0.0529(12) Uani 1 1 d . . . H9 H 0.6421(6) 0.1491(7) 0.4108(5) 0.0572(13) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0272(11) 0.0228(12) 0.071(2) -0.0004(10) 0.0076(12) -0.0004(7) O3 0.0246(11) 0.0214(10) 0.076(2) -0.0044(11) 0.0072(13) 0.0004(7) O4 0.0282(12) 0.0227(12) 0.141(4) -0.0033(15) 0.0033(17) 0.0017(8) N1 0.0231(7) 0.0288(7) 0.0596(12) 0.0024(7) 0.0065(7) 0.0025(5) N2 0.0242(7) 0.0270(7) 0.0600(12) -0.0020(7) 0.0068(7) -0.0003(6) C1 0.0218(9) 0.0231(8) 0.0446(15) 0.0000(8) 0.0064(8) 0.0007(6) C2 0.0394(12) 0.0297(11) 0.070(2) 0.0052(12) 0.0143(14) 0.0065(9) H3 0.274(12) 0.046(4) 0.095(7) -0.014(4) 0.099(7) -0.007(5) H4 0.076(5) 0.045(4) 0.342(17) 0.039(6) -0.038(7) 0.004(3) H5 0.153(7) 0.042(3) 0.148(8) 0.019(4) 0.089(6) -0.002(4) C3 0.0285(12) 0.0430(14) 0.068(2) 0.0016(13) 0.0096(13) -0.0054(9) H6 0.119(9) 0.40(3) 0.061(7) 0.040(9) -0.021(6) -0.171(13) H7 0.070(6) 0.224(15) 0.183(13) -0.084(10) 0.067(7) -0.061(6) H8 0.058(5) 0.062(4) 0.47(3) 0.044(10) 0.004(9) -0.016(4) C4 0.0235(9) 0.0217(9) 0.0598(17) -0.0016(9) 0.0103(9) 0.0007(7) H2 0.028(2) 0.039(2) 0.088(5) -0.006(2) 0.008(2) 0.0059(15) H1 0.037(2) 0.039(2) 0.076(4) -0.005(2) 0.013(2) -0.0030(16) H9 0.050(3) 0.041(2) 0.078(4) -0.004(2) 0.021(2) -0.0124(19) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.277(3) . ? O3 C4 1.282(3) . ? O4 C4 1.209(3) . ? N1 C1 1.335(2) . ? N1 C2 1.454(3) . ? N1 C3 1.466(3) . ? N2 C1 1.332(3) . ? C4 C4 1.552(4) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 122.05(17) . . ? C1 N1 C3 120.06(18) . . ? C2 N1 C3 117.86(18) . . ? O1 C1 N2 121.17(18) . . ? O1 C1 N1 118.28(18) . . ? N2 C1 N1 120.55(17) . . ? O4 C4 O3 125.9(2) . . ? O4 C4 C4 119.8(3) . 3_756 ? O3 C4 C4 114.3(2) . 3_756 ? _refine_diff_density_max 0.076 _refine_diff_density_min -0.095 _refine_diff_density_rms 0.014 # Attachment 'NN-DMU_oxalic_225K_neutron_CIF.cif' data_dmuox_225 _database_code_depnum_ccdc_archive 'CCDC 894622' #TrackingRef 'NN-DMU_oxalic_225K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.820(5) _cell_length_b 6.450(5) _cell_length_c 13.710(5) _cell_angle_alpha 90.00 _cell_angle_beta 111.660(10) _cell_angle_gamma 90.00 _cell_volume 642.7(7) _cell_formula_units_Z 2 _cell_measurement_temperature 225 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.375 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 225 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_reflns_number 5604 _diffrn_reflns_av_R_equivalents 0.1627 _diffrn_reflns_av_sigmaI/netI 0.0943 _diffrn_reflns_limit_h_min -10 _diffrn_reflns_limit_h_max 10 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_k_max 9 _diffrn_reflns_limit_l_min -15 _diffrn_reflns_limit_l_max 16 _reflns_number_total 1240 _reflns_number_gt 755 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.69 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 2.3(6) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 1240 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.1302 _refine_ls_R_factor_gt 0.0649 _refine_ls_wR_factor_ref 0.1248 _refine_ls_wR_factor_gt 0.1147 _refine_ls_goodness_of_fit_ref 1.695 _refine_ls_restrained_S_all 1.695 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.5005(4) 0.2553(3) 0.3802(3) 0.0481(8) Uani 1 1 d . . . O3 O 0.7603(4) 0.0161(4) 0.4379(3) 0.0474(9) Uani 1 1 d . . . O4 O 0.9679(4) 0.2641(4) 0.5002(4) 0.0787(16) Uani 1 1 d . . . N1 N 0.3479(2) 0.5559(2) 0.34035(16) 0.0433(5) Uani 1 1 d . . . N2 N 0.6666(2) 0.5536(2) 0.41242(17) 0.0449(6) Uani 1 1 d . . . C1 C 0.5074(3) 0.4527(3) 0.3784(2) 0.0359(6) Uani 1 1 d . . . C2 C 0.3414(4) 0.7808(4) 0.3356(3) 0.0526(8) Uani 1 1 d . . . H3 H 0.388(2) 0.8479(12) 0.4076(9) 0.139(4) Uani 1 1 d . . . H4 H 0.2162(13) 0.8302(14) 0.2932(12) 0.196(7) Uani 1 1 d . . . H5 H 0.4315(16) 0.8417(11) 0.3031(7) 0.114(3) Uani 1 1 d . . . C3 C 0.1733(4) 0.4430(5) 0.3047(4) 0.0529(8) Uani 1 1 d . . . H6 H 0.1051(19) 0.461(3) 0.2340(10) 0.201(10) Uani 1 1 d . . . H7 H 0.0938(17) 0.490(2) 0.3414(14) 0.170(7) Uani 1 1 d . . . H8 H 0.1883(12) 0.3018(17) 0.3182(18) 0.226(11) Uani 1 1 d . . . C4 C 0.9248(3) 0.0849(3) 0.4825(2) 0.0405(6) Uani 1 1 d . . . H2 H 0.7846(7) 0.4710(7) 0.4432(6) 0.0667(19) Uani 1 1 d . . . H1 H 0.6790(7) 0.7106(8) 0.4165(5) 0.0570(14) Uani 1 1 d . . . H9 H 0.6432(7) 0.1483(8) 0.4100(5) 0.0606(14) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0304(12) 0.0250(13) 0.080(2) -0.0024(12) 0.0094(14) 0.0004(8) O3 0.0326(14) 0.0238(12) 0.078(3) -0.0061(12) 0.0117(15) 0.0014(8) O4 0.0329(14) 0.0260(14) 0.152(5) -0.0079(16) 0.0051(19) 0.0015(9) N1 0.0263(8) 0.0317(8) 0.0638(14) 0.0029(8) 0.0074(8) 0.0031(6) N2 0.0262(8) 0.0294(8) 0.0714(15) -0.0015(8) 0.0091(8) 0.0010(6) C1 0.0274(10) 0.0254(9) 0.0500(17) 0.0021(10) 0.0087(10) 0.0008(8) C2 0.0424(14) 0.0360(13) 0.074(3) 0.0070(14) 0.0156(15) 0.0081(10) H3 0.266(14) 0.045(4) 0.121(9) -0.013(5) 0.091(9) -0.005(6) H4 0.074(6) 0.056(4) 0.362(18) 0.029(8) -0.032(8) 0.012(4) H5 0.190(9) 0.050(4) 0.135(8) 0.019(4) 0.098(7) -0.002(5) C3 0.0293(13) 0.0502(16) 0.072(3) 0.0001(16) 0.0100(15) -0.0057(11) H6 0.112(10) 0.39(3) 0.067(9) 0.034(9) -0.009(7) -0.150(13) H7 0.090(8) 0.218(15) 0.235(18) -0.101(11) 0.098(10) -0.070(8) H8 0.050(5) 0.065(5) 0.49(3) 0.023(10) 0.009(10) -0.020(4) C4 0.0286(11) 0.0240(10) 0.0638(17) -0.0004(10) 0.0112(11) 0.0020(7) H2 0.028(2) 0.042(2) 0.116(6) -0.012(3) 0.010(3) 0.0050(17) H1 0.041(2) 0.038(2) 0.086(4) -0.005(2) 0.017(2) -0.0029(17) H9 0.047(3) 0.045(2) 0.083(4) -0.007(3) 0.017(3) -0.0113(19) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.275(3) . ? O3 C4 1.283(4) . ? O4 C4 1.203(4) . ? N1 C1 1.338(3) . ? N1 C2 1.452(3) . ? N1 C3 1.463(3) . ? N2 C1 1.328(3) . ? C4 C4 1.548(4) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 121.78(19) . . ? C1 N1 C3 120.2(2) . . ? C2 N1 C3 118.0(2) . . ? O1 C1 N2 121.6(2) . . ? O1 C1 N1 117.7(2) . . ? N2 C1 N1 120.74(17) . . ? O4 C4 O3 125.8(2) . . ? O4 C4 C4 119.6(3) . 3_756 ? O3 C4 C4 114.6(2) . 3_756 ? _refine_diff_density_max 0.070 _refine_diff_density_min -0.083 _refine_diff_density_rms 0.013 # Attachment 'NN-DMU_oxalic_250K_neutron_CIF.cif' data_dmuox_250 _database_code_depnum_ccdc_archive 'CCDC 894623' #TrackingRef 'NN-DMU_oxalic_250K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.840(5) _cell_length_b 6.460(5) _cell_length_c 13.770(5) _cell_angle_alpha 90.00 _cell_angle_beta 111.940(10) _cell_angle_gamma 90.00 _cell_volume 646.9(7) _cell_formula_units_Z 2 _cell_measurement_temperature 250 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.366 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 250 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_reflns_number 4852 _diffrn_reflns_av_R_equivalents 0.1400 _diffrn_reflns_av_sigmaI/netI 0.0744 _diffrn_reflns_limit_h_min -9 _diffrn_reflns_limit_h_max 9 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_k_max 8 _diffrn_reflns_limit_l_min -15 _diffrn_reflns_limit_l_max 15 _reflns_number_total 965 _reflns_number_gt 664 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.63 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 3.5(7) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 965 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.1024 _refine_ls_R_factor_gt 0.0584 _refine_ls_wR_factor_ref 0.1127 _refine_ls_wR_factor_gt 0.1036 _refine_ls_goodness_of_fit_ref 1.719 _refine_ls_restrained_S_all 1.719 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.5016(4) 0.2552(4) 0.3797(3) 0.0555(10) Uani 1 1 d . . . O3 O 0.7604(5) 0.0173(4) 0.4384(4) 0.0564(11) Uani 1 1 d . . . O4 O 0.9674(5) 0.2637(5) 0.4994(4) 0.0889(19) Uani 1 1 d . . . N1 N 0.3481(2) 0.5553(3) 0.34011(17) 0.0494(6) Uani 1 1 d . . . N2 N 0.6665(3) 0.5539(3) 0.41206(18) 0.0508(6) Uani 1 1 d . . . C1 C 0.5073(3) 0.4521(3) 0.3778(2) 0.0417(7) Uani 1 1 d . . . C2 C 0.3406(4) 0.7803(5) 0.3360(4) 0.0595(10) Uani 1 1 d . . . H3 H 0.390(3) 0.8464(14) 0.4056(10) 0.157(6) Uani 1 1 d . . . H4 H 0.2161(17) 0.8274(15) 0.2935(15) 0.222(9) Uani 1 1 d . . . H5 H 0.4301(18) 0.8432(13) 0.3023(9) 0.130(4) Uani 1 1 d . . . C3 C 0.1744(4) 0.4423(6) 0.3038(4) 0.0621(10) Uani 1 1 d . . . H6 H 0.110(2) 0.460(3) 0.2330(10) 0.207(10) Uani 1 1 d . . . H7 H 0.0966(16) 0.490(2) 0.3432(14) 0.177(7) Uani 1 1 d . . . H8 H 0.1899(14) 0.301(2) 0.3220(19) 0.232(12) Uani 1 1 d . . . C4 C 0.9247(3) 0.0849(3) 0.4821(2) 0.0461(7) Uani 1 1 d . . . H2 H 0.7851(7) 0.4710(8) 0.4437(6) 0.0673(19) Uani 1 1 d . . . H1 H 0.6791(8) 0.7058(9) 0.4167(5) 0.0636(15) Uani 1 1 d . . . H9 H 0.6454(8) 0.1475(8) 0.4110(5) 0.0658(15) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0377(16) 0.0268(16) 0.092(3) -0.0014(13) 0.0128(17) -0.0012(11) O3 0.0345(16) 0.0301(14) 0.094(3) -0.0057(14) 0.0123(17) 0.0023(10) O4 0.0324(14) 0.0309(17) 0.174(6) -0.0039(19) 0.005(2) -0.0010(12) N1 0.0317(9) 0.0370(9) 0.0708(15) 0.0025(9) 0.0092(9) 0.0031(7) N2 0.0313(11) 0.0341(11) 0.0783(16) -0.0028(9) 0.0104(9) 0.0001(8) C1 0.0292(12) 0.0310(12) 0.0590(19) -0.0017(11) 0.0096(11) 0.0006(9) C2 0.0517(18) 0.0384(17) 0.084(3) 0.0062(17) 0.0205(18) 0.0070(12) H3 0.320(18) 0.051(5) 0.124(10) -0.011(5) 0.110(10) -0.002(7) H4 0.103(8) 0.049(4) 0.40(2) 0.038(8) -0.038(11) 0.008(5) H5 0.194(10) 0.061(4) 0.167(10) 0.027(5) 0.105(8) -0.009(6) C3 0.0351(17) 0.055(2) 0.089(3) 0.0009(18) 0.0143(19) -0.0058(14) H6 0.133(10) 0.39(3) 0.059(8) 0.017(9) -0.007(7) -0.165(14) H7 0.079(7) 0.232(18) 0.241(17) -0.096(12) 0.085(9) -0.057(8) H8 0.069(6) 0.070(6) 0.48(3) 0.049(11) 0.011(11) -0.020(5) C4 0.0329(12) 0.0261(12) 0.0757(19) -0.0013(11) 0.0162(12) -0.0008(9) H2 0.034(3) 0.047(3) 0.109(6) -0.005(3) 0.013(3) 0.002(2) H1 0.047(2) 0.044(3) 0.092(5) -0.002(3) 0.018(3) -0.006(2) H9 0.066(4) 0.047(3) 0.083(4) -0.010(3) 0.027(3) -0.014(3) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.273(3) . ? O3 C4 1.278(4) . ? O4 C4 1.201(4) . ? N1 C1 1.337(3) . ? N1 C2 1.455(4) . ? N1 C3 1.459(4) . ? N2 C1 1.331(3) . ? C4 C4 1.551(4) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 122.1(2) . . ? C1 N1 C3 120.0(2) . . ? C2 N1 C3 117.9(2) . . ? O1 C1 N2 121.4(2) . . ? O1 C1 N1 118.1(2) . . ? N2 C1 N1 120.4(2) . . ? O4 C4 O3 125.4(3) . . ? O4 C4 C4 119.7(3) . 3_756 ? O3 C4 C4 114.9(3) . 3_756 ? _refine_diff_density_max 0.049 _refine_diff_density_min -0.060 _refine_diff_density_rms 0.010 # Attachment 'NN-DMU_oxalic_275K_neutron_CIF.cif' data_dmuox_275 _database_code_depnum_ccdc_archive 'CCDC 894624' #TrackingRef 'NN-DMU_oxalic_275K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.870(5) _cell_length_b 6.470(5) _cell_length_c 13.830(5) _cell_angle_alpha 90.00 _cell_angle_beta 112.200(10) _cell_angle_gamma 90.00 _cell_volume 652.0(7) _cell_formula_units_Z 2 _cell_measurement_temperature 275 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.355 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 275 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_reflns_number 4233 _diffrn_reflns_av_R_equivalents 0.1470 _diffrn_reflns_av_sigmaI/netI 0.0805 _diffrn_reflns_limit_h_min -9 _diffrn_reflns_limit_h_max 9 _diffrn_reflns_limit_k_min -7 _diffrn_reflns_limit_k_max 7 _diffrn_reflns_limit_l_min -14 _diffrn_reflns_limit_l_max 15 _reflns_number_total 916 _reflns_number_gt 582 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.62 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 3.4(7) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 916 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.1107 _refine_ls_R_factor_gt 0.0578 _refine_ls_wR_factor_ref 0.1071 _refine_ls_wR_factor_gt 0.0974 _refine_ls_goodness_of_fit_ref 1.573 _refine_ls_restrained_S_all 1.573 _refine_ls_shift/su_max 0.000 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.5016(4) 0.2551(4) 0.3792(3) 0.0622(11) Uani 1 1 d . . . O3 O 0.7609(5) 0.0169(4) 0.4379(4) 0.0631(13) Uani 1 1 d . . . O4 O 0.9672(5) 0.2627(5) 0.4987(4) 0.101(2) Uani 1 1 d . . . N1 N 0.3489(2) 0.5548(3) 0.34037(18) 0.0558(7) Uani 1 1 d . . . N2 N 0.6661(3) 0.5538(4) 0.41198(19) 0.0577(7) Uani 1 1 d . . . C1 C 0.5075(3) 0.4521(3) 0.3779(2) 0.0468(7) Uani 1 1 d . . . C2 C 0.3403(5) 0.7795(5) 0.3364(4) 0.0670(12) Uani 1 1 d . . . H3 H 0.386(3) 0.8451(16) 0.4067(10) 0.165(6) Uani 1 1 d . . . H4 H 0.222(2) 0.8272(15) 0.2918(15) 0.228(10) Uani 1 1 d . . . H5 H 0.4304(18) 0.8451(12) 0.3045(10) 0.143(4) Uani 1 1 d . . . C3 C 0.1752(5) 0.4412(7) 0.3047(4) 0.0674(11) Uani 1 1 d . . . H6 H 0.101(2) 0.471(3) 0.2328(12) 0.213(10) Uani 1 1 d . . . H7 H 0.101(2) 0.475(3) 0.3444(14) 0.184(8) Uani 1 1 d . . . H8 H 0.1910(15) 0.301(2) 0.314(2) 0.256(14) Uani 1 1 d . . . C4 C 0.9251(3) 0.0850(3) 0.4820(2) 0.0514(8) Uani 1 1 d . . . H2 H 0.7835(8) 0.4706(9) 0.4438(6) 0.077(2) Uani 1 1 d . . . H1 H 0.6787(8) 0.7051(11) 0.4160(6) 0.0722(17) Uani 1 1 d . . . H9 H 0.6468(8) 0.1470(8) 0.4118(5) 0.0733(17) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0429(16) 0.0286(17) 0.104(3) -0.0012(15) 0.0147(18) -0.0005(11) O3 0.0381(17) 0.0365(16) 0.103(4) -0.0042(16) 0.0133(18) 0.0013(11) O4 0.0400(16) 0.0322(19) 0.196(7) -0.008(2) 0.005(2) 0.0012(12) N1 0.0344(11) 0.0419(10) 0.0815(17) 0.0027(10) 0.0111(10) 0.0034(7) N2 0.0358(12) 0.0403(12) 0.0883(18) -0.0025(11) 0.0137(10) 0.0002(9) C1 0.0363(13) 0.0327(12) 0.064(2) -0.0004(12) 0.0104(12) 0.0016(9) C2 0.054(2) 0.0433(19) 0.098(4) 0.006(2) 0.022(2) 0.0064(14) H3 0.36(2) 0.058(5) 0.117(9) -0.003(5) 0.130(11) 0.008(7) H4 0.133(10) 0.047(5) 0.38(2) 0.035(8) -0.045(12) 0.009(5) H5 0.179(11) 0.059(5) 0.221(13) 0.029(6) 0.110(10) -0.008(5) C3 0.0381(18) 0.064(2) 0.087(4) 0.002(2) 0.0095(18) -0.0055(15) H6 0.125(11) 0.36(3) 0.100(11) 0.053(11) -0.023(9) -0.136(13) H7 0.104(10) 0.27(2) 0.209(18) -0.084(13) 0.091(11) -0.078(10) H8 0.064(6) 0.076(6) 0.55(4) 0.011(12) 0.028(12) -0.025(5) C4 0.0405(15) 0.0312(13) 0.079(2) -0.0030(13) 0.0185(13) -0.0008(10) H2 0.042(3) 0.058(3) 0.119(7) 0.002(3) 0.017(3) 0.003(3) H1 0.046(2) 0.052(3) 0.109(5) -0.008(3) 0.017(3) -0.005(2) H9 0.072(4) 0.047(3) 0.094(5) -0.008(3) 0.024(3) -0.015(3) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.276(4) . ? O3 C4 1.280(4) . ? O4 C4 1.195(4) . ? N1 C1 1.334(3) . ? N1 C2 1.455(4) . ? N1 C3 1.464(4) . ? N2 C1 1.330(3) . ? C4 C4 1.550(5) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 122.4(2) . . ? C1 N1 C3 119.9(2) . . ? C2 N1 C3 117.7(3) . . ? O1 C1 N2 121.6(2) . . ? O1 C1 N1 118.0(2) . . ? N2 C1 N1 120.4(2) . . ? O4 C4 O3 125.4(3) . . ? O4 C4 C4 119.9(3) . 3_756 ? O3 C4 C4 114.7(3) . 3_756 ? _refine_diff_density_max 0.044 _refine_diff_density_min -0.053 _refine_diff_density_rms 0.010 # Attachment 'NN-DMU_oxalic_300K_X-ray_CIF.cif' data_dmuox_300k _database_code_depnum_ccdc_archive 'CCDC 894625' #TrackingRef 'NN-DMU_oxalic_300K_X-ray_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C4 H9 N2 O3' _chemical_formula_weight 133.13 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.8936(4) _cell_length_b 6.4695(3) _cell_length_c 13.8871(7) _cell_angle_alpha 90.00 _cell_angle_beta 112.474(3) _cell_angle_gamma 90.00 _cell_volume 655.32(6) _cell_formula_units_Z 4 _cell_measurement_temperature 300 _cell_measurement_reflns_used 4638 _cell_measurement_theta_min 6.30 _cell_measurement_theta_max 55.12 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 0.4 _exptl_crystal_size_mid 0.2 _exptl_crystal_size_min 0.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.349 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 284 _exptl_absorpt_coefficient_mu 0.115 _exptl_absorpt_correction_type multi-scan _exptl_absorpt_correction_T_min 0.2644 _exptl_absorpt_correction_T_max 1.0000 _exptl_absorpt_process_details 'ABSCOR, Rigaku 1995' _exptl_special_details ; ? ; _diffrn_ambient_temperature 300 _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'Rigaku R-AXIS RAPID IP Image Plate' _diffrn_measurement_method 'Image plate' _diffrn_detector_area_resol_mean ? _diffrn_standards_number ? _diffrn_standards_interval_count ? _diffrn_standards_interval_time ? _diffrn_standards_decay_% ? _diffrn_reflns_number 8144 _diffrn_reflns_av_R_equivalents 0.0168 _diffrn_reflns_av_sigmaI/netI 0.0132 _diffrn_reflns_limit_h_min -10 _diffrn_reflns_limit_h_max 10 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_k_max 8 _diffrn_reflns_limit_l_min -18 _diffrn_reflns_limit_l_max 18 _diffrn_reflns_theta_min 3.17 _diffrn_reflns_theta_max 27.46 _reflns_number_total 1487 _reflns_number_gt 1025 _reflns_threshold_expression >2\s(I) _computing_data_collection 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_cell_refinement 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_data_reduction 'CrystalClear 1.4.0 (Rigaku, 2008)' _computing_structure_solution 'SHELXS-97 (Sheldrick, 2008)' _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.1005P)^2^+0.0561P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 0.008(6) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 1487 _refine_ls_number_parameters 95 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0684 _refine_ls_R_factor_gt 0.0521 _refine_ls_wR_factor_ref 0.1795 _refine_ls_wR_factor_gt 0.1663 _refine_ls_goodness_of_fit_ref 1.118 _refine_ls_restrained_S_all 1.118 _refine_ls_shift/su_max 0.026 _refine_ls_shift/su_mean 0.001 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.50295(18) 0.25554(19) 0.37984(11) 0.0721(5) Uani 1 1 d . . . O3 O 0.76191(16) 0.0170(2) 0.43841(12) 0.0726(5) Uani 1 1 d . . . O4 O 0.9674(2) 0.2628(2) 0.49836(19) 0.1154(8) Uani 1 1 d . . . N1 N 0.34960(19) 0.5545(2) 0.34051(12) 0.0618(5) Uani 1 1 d . . . N2 N 0.6666(2) 0.5530(3) 0.41198(13) 0.0649(5) Uani 1 1 d . . . C1 C 0.5078(2) 0.4513(3) 0.37785(12) 0.0534(5) Uani 1 1 d . . . C2 C 0.3419(3) 0.7783(3) 0.33571(18) 0.0753(6) Uani 1 1 d . . . H2A H 0.3777 0.8334 0.4049 0.113 Uiso 1 1 calc R . . H2B H 0.2191 0.8215 0.2944 0.113 Uiso 1 1 calc R . . H2C H 0.4238 0.8283 0.3046 0.113 Uiso 1 1 calc R . . C3 C 0.1773(3) 0.4411(4) 0.3044(2) 0.0788(6) Uani 1 1 d . . . H3A H 0.1820 0.3314 0.2590 0.118 Uiso 1 1 calc R . . H3B H 0.0784 0.5332 0.2674 0.118 Uiso 1 1 calc R . . H3C H 0.1579 0.3840 0.3632 0.118 Uiso 1 1 calc R . . C4 C 0.9253(2) 0.0847(2) 0.48250(14) 0.0586(5) Uani 1 1 d . . . H2 H 0.762(3) 0.468(4) 0.4422(15) 0.070 Uiso 1 1 d . . . H1 H 0.669(3) 0.687(3) 0.4149(16) 0.070 Uiso 1 1 d . . . H9 H 0.657(5) 0.147(5) 0.412(2) 0.134(10) Uiso 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0487(7) 0.0431(7) 0.1127(11) -0.0007(6) 0.0175(7) -0.0011(5) O3 0.0456(8) 0.0430(7) 0.1160(11) -0.0050(6) 0.0161(7) 0.0009(5) O4 0.0485(9) 0.0391(8) 0.224(2) -0.0016(9) 0.0127(10) 0.0014(6) N1 0.0416(8) 0.0507(8) 0.0840(10) 0.0036(7) 0.0137(7) 0.0018(6) N2 0.0445(8) 0.0434(8) 0.0962(11) -0.0009(7) 0.0152(7) -0.0003(7) C1 0.0447(9) 0.0457(8) 0.0658(10) -0.0014(7) 0.0166(7) 0.0006(7) C2 0.0624(12) 0.0544(11) 0.1020(15) 0.0085(9) 0.0234(11) 0.0132(8) C3 0.0443(10) 0.0749(13) 0.1037(15) 0.0020(11) 0.0133(9) -0.0037(9) C4 0.0470(10) 0.0411(8) 0.0849(12) -0.0011(7) 0.0222(8) -0.0009(7) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.268(2) . ? O3 C4 1.275(2) . ? O4 C4 1.196(2) . ? N1 C1 1.334(2) . ? N1 C2 1.450(3) . ? N1 C3 1.455(2) . ? N2 C1 1.332(2) . ? C4 C4 1.546(3) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C2 122.29(15) . . ? C1 N1 C3 119.66(17) . . ? C2 N1 C3 118.04(15) . . ? O1 C1 N2 121.17(15) . . ? O1 C1 N1 118.47(15) . . ? N2 C1 N1 120.36(17) . . ? O4 C4 O3 125.30(16) . . ? O4 C4 C4 120.03(18) . 3_756 ? O3 C4 C4 114.67(17) . 3_756 ? _diffrn_measured_fraction_theta_max 0.996 _diffrn_reflns_theta_full 27.46 _diffrn_measured_fraction_theta_full 0.996 _refine_diff_density_max 0.236 _refine_diff_density_min -0.173 _refine_diff_density_rms 0.043 # Attachment 'NN-DMU_oxalic_300K_neutron_CIF.cif' data_dmuox_300 _database_code_depnum_ccdc_archive 'CCDC 894626' #TrackingRef 'NN-DMU_oxalic_300K_neutron_CIF.cif' _audit_creation_method SHELXL-97 _chemical_name_systematic ; bis(N,N-Dimethylurea) ethanedioic acid ; _chemical_name_common ; bis(N,N-Dimethylurea) oxalic acid ; _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C8 H18 N4 O6' _chemical_formula_weight 266.00 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' N N 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P21/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 7.890(5) _cell_length_b 6.470(5) _cell_length_c 13.890(5) _cell_angle_alpha 90.00 _cell_angle_beta 112.470(10) _cell_angle_gamma 90.00 _cell_volume 655.2(7) _cell_formula_units_Z 2 _cell_measurement_temperature 300 _cell_measurement_reflns_used 250 _exptl_crystal_description prism _exptl_crystal_colour colourless _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.2 _exptl_crystal_size_min 1.2 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.348 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 12 _exptl_absorpt_coefficient_mu 0.000 _exptl_absorpt_correction_type none _exptl_special_details ; For peak integration a local UB matrix was refined for each pattern, using approximately 250 reflections. Hence _cell_measurement_reflns_used 250 Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.8-5.2 Angstroms. ; _diffrn_ambient_temperature 300 _diffrn_radiation_wavelength 0.80-5.20 _diffrn_radiation_type neutron _diffrn_radiation_source 'ILL reactor source, thermal guide' _diffrn_radiation_monochromator none _diffrn_measurement_device_type VIVALDI _diffrn_measurement_method 'Laue patterns at 10 orientations' _diffrn_detector_area_resol_mean 0.7 _diffrn_standards_number none _diffrn_reflns_number 4011 _diffrn_reflns_av_R_equivalents 0.1355 _diffrn_reflns_av_sigmaI/netI 0.0696 _diffrn_reflns_limit_h_min -9 _diffrn_reflns_limit_h_max 9 _diffrn_reflns_limit_k_min -7 _diffrn_reflns_limit_k_max 7 _diffrn_reflns_limit_l_min -14 _diffrn_reflns_limit_l_max 15 _reflns_number_total 804 _reflns_number_gt 540 _reflns_threshold_expression >2\s(I) _computing_data_collection 'VIVALDI (MAATEL)' _computing_cell_refinement 'lauegen (CCP4)' _computing_data_reduction 'argonne_boxes, laue4 (Piltz, 2011)' _computing_structure_solution ? _computing_structure_refinement 'SHELXL-97 (Sheldrick, 2008)' _computing_molecular_graphics 'Mercury (McRae, 2006)' _computing_publication_material 'WINGX (Farrugia, 1999)' _refine_special_details ; The variable wavelength nature of the data collection procedure means that meaningful values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given instead the following limits are given _diffrn_reflns_sin(theta)/lambda_min 0.03 _diffrn_reflns_sin(theta)/lambda_max 0.58 _refine_diff_density_max/min is given in Fermi per Angstrom cubed not electrons per angstrom cubed. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > 2\s(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0300P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens difmap _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 2.1(4) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 804 _refine_ls_number_parameters 164 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0962 _refine_ls_R_factor_gt 0.0567 _refine_ls_wR_factor_ref 0.1044 _refine_ls_wR_factor_gt 0.0969 _refine_ls_goodness_of_fit_ref 1.591 _refine_ls_restrained_S_all 1.591 _refine_ls_shift/su_max 0.001 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group O1 O 0.5021(5) 0.2550(4) 0.3798(4) 0.0706(13) Uani 1 1 d . . . O3 O 0.7599(5) 0.0170(4) 0.4390(4) 0.0683(13) Uani 1 1 d . . . O4 O 0.9691(5) 0.2627(5) 0.4979(5) 0.113(3) Uani 1 1 d . . . N1 N 0.3492(3) 0.5536(3) 0.34083(19) 0.0613(7) Uani 1 1 d . . . N2 N 0.6669(3) 0.5535(4) 0.4120(2) 0.0628(8) Uani 1 1 d . . . C1 C 0.5081(3) 0.4511(4) 0.3781(3) 0.0527(8) Uani 1 1 d . . . C2 C 0.3408(5) 0.7798(6) 0.3366(5) 0.0719(12) Uani 1 1 d . . . H3 H 0.384(3) 0.8421(17) 0.4052(12) 0.178(7) Uani 1 1 d . . . H4 H 0.2261(19) 0.8282(17) 0.2910(17) 0.234(10) Uani 1 1 d . . . H5 H 0.429(2) 0.8433(13) 0.3052(11) 0.156(5) Uani 1 1 d . . . C3 C 0.1769(5) 0.4401(8) 0.3036(5) 0.0749(13) Uani 1 1 d . . . H6 H 0.108(3) 0.458(4) 0.2336(11) 0.223(12) Uani 1 1 d . . . H7 H 0.095(2) 0.494(2) 0.3408(18) 0.190(8) Uani 1 1 d . . . H8 H 0.1899(18) 0.306(3) 0.323(2) 0.250(13) Uani 1 1 d . . . C4 C 0.9254(4) 0.0842(3) 0.4825(3) 0.0575(9) Uani 1 1 d . . . H2 H 0.7853(8) 0.4725(9) 0.4429(6) 0.079(2) Uani 1 1 d . . . H1 H 0.6788(8) 0.7052(13) 0.4164(5) 0.0764(19) Uani 1 1 d . . . H9 H 0.6487(9) 0.1469(9) 0.4120(6) 0.0799(19) Uani 1 1 d . . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 O1 0.0483(19) 0.0286(19) 0.121(4) -0.0015(16) 0.017(2) -0.0024(12) O3 0.043(2) 0.0404(18) 0.109(4) -0.0047(18) 0.0154(19) 0.0026(13) O4 0.0393(18) 0.037(2) 0.226(8) -0.006(2) 0.010(3) 0.0017(13) N1 0.0381(11) 0.0473(11) 0.0878(18) 0.0042(11) 0.0122(10) 0.0044(8) N2 0.0399(14) 0.0430(15) 0.0950(19) -0.0034(11) 0.0139(11) 0.0012(11) C1 0.0366(14) 0.0374(14) 0.076(2) 0.0005(13) 0.0122(13) 0.0015(11) C2 0.060(2) 0.048(2) 0.102(4) 0.006(2) 0.024(2) 0.0079(16) H3 0.37(2) 0.063(6) 0.137(11) -0.007(7) 0.138(13) 0.010(9) H4 0.122(10) 0.060(5) 0.40(3) 0.045(10) -0.031(13) 0.004(6) H5 0.201(12) 0.053(5) 0.240(15) 0.032(6) 0.114(11) -0.006(6) C3 0.043(2) 0.069(2) 0.103(4) 0.004(2) 0.017(2) -0.0036(18) H6 0.158(13) 0.39(3) 0.070(10) 0.018(11) -0.010(9) -0.167(16) H7 0.095(9) 0.207(16) 0.30(2) -0.078(13) 0.106(12) -0.033(7) H8 0.092(8) 0.097(8) 0.47(4) 0.043(14) 0.003(13) -0.048(7) C4 0.0442(17) 0.0319(14) 0.092(2) -0.0020(14) 0.0207(15) 0.0007(11) H2 0.038(3) 0.061(3) 0.123(7) -0.003(3) 0.015(3) 0.003(3) H1 0.054(3) 0.055(4) 0.113(6) 0.003(3) 0.024(3) -0.005(3) H9 0.078(5) 0.052(3) 0.108(5) -0.012(3) 0.034(4) -0.016(3) _geom_special_details ; All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag O1 C1 1.270(4) . ? O3 C4 1.287(5) . ? O4 C4 1.201(4) . ? N1 C1 1.335(3) . ? N1 C3 1.455(4) . ? N1 C2 1.465(5) . ? N2 C1 1.335(4) . ? C4 C4 1.540(5) 3_756 ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C1 N1 C3 119.9(3) . . ? C1 N1 C2 122.2(2) . . ? C3 N1 C2 117.9(3) . . ? O1 C1 N2 121.7(3) . . ? O1 C1 N1 117.9(3) . . ? N2 C1 N1 120.4(2) . . ? O4 C4 O3 125.4(3) . . ? O4 C4 C4 119.4(3) . 3_756 ? O3 C4 C4 115.2(3) . 3_756 ? _refine_diff_density_max 0.039 _refine_diff_density_min -0.049 _refine_diff_density_rms 0.009