# Supplementary Material (ESI) for Chemical Communications # This journal is © The Royal Society of Chemistry 2005 data_global _journal_coden_Cambridge 182 loop_ _publ_author_name 'W. Jones' 'Graeme Day' 'W.D.Sam Motherwell' 'Andrew V. Trask' _publ_contact_author_name 'William Jones' _publ_contact_author_address ; Department of Chemistry University of Cambridge Lensfield Road Cambridge CB2 1EW UNITED KINGDOM ; _publ_contact_author_email WJ10@CAM.AC.UK _publ_requested_journal 'Chemical Communications' _publ_section_title ; Investigating the latent polymorphism of maleic acid ; data_FormI _database_code_depnum_ccdc_archive 'CCDC 285153' _audit_creation_method SHELXL-97 _chemical_name_systematic 'cis-ethene-1,2-dicarboxylic acid' _chemical_name_common 'Maleic Acid' _chemical_melting_point ? _chemical_formula_moiety 'C4 H4 O4' _chemical_formula_sum 'C4 H4 O4' _chemical_formula_weight 116.07 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' 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 'P 21/c' _symmetry_int_tables_number 14 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 7.4749(8) _cell_length_b 10.0849(12) _cell_length_c 7.5465(7) _cell_angle_alpha 90.00 _cell_angle_beta 124.423(6) _cell_angle_gamma 90.00 _cell_volume 469.26(9) _cell_formula_units_Z 4 _cell_measurement_temperature 180(2) _cell_measurement_reflns_used 6066 _cell_measurement_theta_min 1.00 _cell_measurement_theta_max 27.48 _exptl_crystal_description rod _exptl_crystal_colour colourless _exptl_crystal_size_max 0.23 _exptl_crystal_size_mid 0.12 _exptl_crystal_size_min 0.12 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.643 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 240 _exptl_absorpt_coefficient_mu 0.152 _exptl_absorpt_correction_type multi-scan _exptl_absorpt_correction_T_min 0.863 _exptl_absorpt_correction_T_max 0.991 _exptl_absorpt_process_details ; multi-scan from symmetry-related measurements Sortav (Blessing 1995) ; _exptl_special_details ; ? ; _diffrn_ambient_temperature 180(2) _diffrn_radiation_probe x-ray _diffrn_radiation_type MoK\a _diffrn_radiation_wavelength 0.71073 _diffrn_source 'fine-focus sealed tube' _diffrn_measurement_device_type 'Nonius Kappa CCD' _diffrn_measurement_method 'Thin slice \w and \f scans' _diffrn_reflns_number 2647 _diffrn_reflns_av_R_equivalents 0.0268 _diffrn_reflns_av_sigmaI/netI 0.0425 _diffrn_reflns_limit_h_min -9 _diffrn_reflns_limit_h_max 9 _diffrn_reflns_limit_k_min -11 _diffrn_reflns_limit_k_max 13 _diffrn_reflns_limit_l_min -9 _diffrn_reflns_limit_l_max 9 _diffrn_reflns_theta_min 3.67 _diffrn_reflns_theta_max 27.46 _reflns_number_total 1061 _reflns_number_gt 847 _reflns_threshold_expression >2sigma(I) _computing_data_collection 'Collect (Nonius B.V. 1998)' _computing_cell_refinement 'HKL Scalepack (Otwinowski & Minor 1997)' _computing_data_reduction ; HKL Denzo and Scalepack (Otwinowski & Minor 1997) ; _computing_structure_solution 'SIR-92 (Altomare et al. 1994)' _computing_structure_refinement 'SHELXL-97 (Sheldrick 1997)' _computing_publication_material 'SHELXL-97 (Sheldrick 1997)' _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^ > 2sigma(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^)+(0.0532P)^2^+0.0582P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 1061 _refine_ls_number_parameters 79 _refine_ls_number_restraints 2 _refine_ls_R_factor_all 0.0510 _refine_ls_R_factor_gt 0.0387 _refine_ls_wR_factor_ref 0.1064 _refine_ls_wR_factor_gt 0.0984 _refine_ls_goodness_of_fit_ref 1.068 _refine_ls_restrained_S_all 1.068 _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 C1 C 0.4707(2) 0.34938(15) 0.2506(2) 0.0288(4) Uani 1 1 d . . . C2 C 0.3080(2) 0.43409(13) 0.2494(2) 0.0299(4) Uani 1 1 d . . . H2 H 0.3281 0.5271 0.2488 0.036 Uiso 1 1 calc R . . C3 C 0.1367(2) 0.39621(15) 0.2491(2) 0.0294(3) Uani 1 1 d . . . H3 H 0.0527 0.4675 0.2476 0.035 Uiso 1 1 calc R . . C4 C 0.0537(2) 0.26250(15) 0.2507(2) 0.0286(4) Uani 1 1 d . . . O11 O 0.62132(17) 0.41888(10) 0.25577(18) 0.0380(3) Uani 1 1 d D . . H11 H 0.720(3) 0.3572(17) 0.253(3) 0.046 Uiso 1 1 d D . . O12 O 0.46761(17) 0.22795(10) 0.24615(18) 0.0361(3) Uani 1 1 d . . . O41 O 0.15186(16) 0.15437(10) 0.25322(18) 0.0348(3) Uani 1 1 d D . . H41 H 0.276(2) 0.1806(17) 0.249(2) 0.042 Uiso 1 1 d D . . O42 O -0.10909(19) 0.25246(11) 0.2515(2) 0.0390(3) 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 C1 0.0285(7) 0.0248(8) 0.0369(7) 0.0003(6) 0.0208(6) -0.0006(6) C2 0.0336(8) 0.0191(7) 0.0408(8) -0.0003(6) 0.0234(6) -0.0002(6) C3 0.0311(7) 0.0217(7) 0.0388(7) 0.0007(6) 0.0219(6) 0.0042(6) C4 0.0280(7) 0.0265(8) 0.0358(7) -0.0001(6) 0.0207(6) 0.0007(6) O11 0.0365(6) 0.0260(6) 0.0633(7) -0.0010(5) 0.0353(6) -0.0021(5) O12 0.0373(7) 0.0219(6) 0.0602(7) -0.0001(5) 0.0343(6) 0.0013(4) O41 0.0374(6) 0.0211(6) 0.0577(7) 0.0004(5) 0.0340(5) 0.0002(4) O42 0.0363(6) 0.0312(6) 0.0626(7) 0.0005(5) 0.0357(6) -0.0003(5) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 C1 O12 1.2250(18) . ? C1 O11 1.3074(17) . ? C1 C2 1.4825(19) . ? C2 C3 1.335(2) . ? C2 H2 0.9500 . ? C3 C4 1.487(2) . ? C3 H3 0.9500 . ? C4 O42 1.2248(19) . ? C4 O41 1.3083(17) . ? O11 H11 0.975(14) . ? O41 H41 0.983(14) . ? 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 O12 C1 O11 122.66(13) . . ? O12 C1 C2 124.95(12) . . ? O11 C1 C2 112.39(13) . . ? C3 C2 C1 128.19(13) . . ? C3 C2 H2 115.9 . . ? C1 C2 H2 115.9 . . ? C2 C3 C4 131.55(14) . . ? C2 C3 H3 114.2 . . ? C4 C3 H3 114.2 . . ? O42 C4 O41 118.78(13) . . ? O42 C4 C3 119.67(12) . . ? O41 C4 C3 121.54(13) . . ? C1 O11 H11 107.9(11) . . ? C4 O41 H41 107.9(10) . . ? 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 O12 C1 C2 C3 1.9(2) . . . . ? O11 C1 C2 C3 -178.45(14) . . . . ? C1 C2 C3 C4 0.3(3) . . . . ? C2 C3 C4 O42 179.50(15) . . . . ? C2 C3 C4 O41 0.1(2) . . . . ? _diffrn_measured_fraction_theta_max 0.993 _diffrn_reflns_theta_full 27.46 _diffrn_measured_fraction_theta_full 0.993 _refine_diff_density_max 0.182 _refine_diff_density_min -0.227 _refine_diff_density_rms 0.047 data_FormII _database_code_depnum_ccdc_archive 'CCDC 285154' _audit_creation_method SHELXL-97 _chemical_name_systematic 'cis-ethene-1,2-dicarboxylic acid' _chemical_name_common 'Maleic Acid' _chemical_melting_point ? _chemical_formula_moiety 'C4 H4 O4' _chemical_formula_sum 'C4 H4 O4' _chemical_formula_weight 116.07 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' 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 Pc loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' 'x, -y, z+1/2' _cell_length_a 3.6933(3) _cell_length_b 7.4840(5) _cell_length_c 8.5933(7) _cell_angle_alpha 90.00 _cell_angle_beta 102.220(3) _cell_angle_gamma 90.00 _cell_volume 232.14(3) _cell_formula_units_Z 2 _cell_measurement_temperature 180(2) _cell_measurement_reflns_used 1177 _cell_measurement_theta_min 1.02 _cell_measurement_theta_max 27.48 _exptl_crystal_description plate _exptl_crystal_colour colourless _exptl_crystal_size_max 0.16 _exptl_crystal_size_mid 0.14 _exptl_crystal_size_min 0.07 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.661 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 120 _exptl_absorpt_coefficient_mu 0.154 _exptl_absorpt_correction_type multi-scan _exptl_absorpt_correction_T_min 0.948 _exptl_absorpt_correction_T_max 0.993 _exptl_absorpt_process_details ; multi-scan from symmetry-related measurements Sortav (Blessing 1995) ; _exptl_special_details ; There is pseudo C-centred orthorhombic cell but R(merge) in this setting is very high! 191 Freidel pairs averaged for the refinement. ; _diffrn_ambient_temperature 180(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_measurement_device_type 'Nonius Kappa CCD' _diffrn_measurement_method 'Thin slice \w and \f scans' _diffrn_reflns_number 1278 _diffrn_reflns_av_R_equivalents 0.0280 _diffrn_reflns_av_sigmaI/netI 0.0367 _diffrn_reflns_limit_h_min -4 _diffrn_reflns_limit_h_max 2 _diffrn_reflns_limit_k_min -9 _diffrn_reflns_limit_k_max 9 _diffrn_reflns_limit_l_min -11 _diffrn_reflns_limit_l_max 10 _diffrn_reflns_theta_min 3.65 _diffrn_reflns_theta_max 27.46 _reflns_number_total 529 _reflns_number_gt 514 _reflns_threshold_expression >2sigma(I) _computing_data_collection 'Collect (Nonius B.V. 1998)' _computing_cell_refinement 'HKL Scalepack (Otwinowski & Minor 1997)' _computing_data_reduction ; HKL Denzo and Scalepack (Otwinowski & Minor 1997) ; _computing_structure_solution 'SIR-92 (Altomare et al. 1994)' _computing_structure_refinement 'SHELXL-97 (Sheldrick 1997)' _computing_publication_material 'SHELXL-97 (Sheldrick 1997)' _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^ > 2sigma(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^)+(0.0293P)^2^+0.0110P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment mixed _refine_ls_extinction_method none _refine_ls_extinction_coef ? _refine_ls_number_reflns 529 _refine_ls_number_parameters 80 _refine_ls_number_restraints 4 _refine_ls_R_factor_all 0.0291 _refine_ls_R_factor_gt 0.0261 _refine_ls_wR_factor_ref 0.0615 _refine_ls_wR_factor_gt 0.0607 _refine_ls_goodness_of_fit_ref 1.101 _refine_ls_restrained_S_all 1.097 _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 C1 C 0.9251(6) 0.4467(2) 0.7379(2) 0.0229(4) Uani 1 1 d . . . O11 O 0.7362(4) 0.35142(19) 0.6217(2) 0.0322(4) Uani 1 1 d D . . H11 H 0.776(11) 0.223(3) 0.639(5) 0.060(9) Uiso 1 1 d D . . O12 O 0.8994(4) 0.60968(17) 0.7313(2) 0.0353(4) Uani 1 1 d . . . C2 C 1.1744(6) 0.3622(3) 0.8778(2) 0.0243(4) Uani 1 1 d . . . H2A H 1.3106 0.4449 0.9516 0.029 Uiso 1 1 calc R . . C3 C 1.2408(5) 0.1901(2) 0.9183(2) 0.0246(4) Uani 1 1 d . . . H3A H 1.4120 0.1691 1.0158 0.030 Uiso 1 1 calc R . . C4 C 1.0803(5) 0.0291(2) 0.8298(2) 0.0243(4) Uani 1 1 d . . . O41 O 1.2137(5) -0.1185(2) 0.9008(2) 0.0337(4) Uani 1 1 d D . . H41 H 1.106(8) -0.228(3) 0.843(3) 0.040 Uiso 1 1 d D . . O42 O 0.8476(4) 0.0302(2) 0.70456(17) 0.0332(4) 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 C1 0.0255(9) 0.0196(8) 0.0224(9) -0.0032(9) 0.0023(8) -0.0020(7) O11 0.0411(8) 0.0219(6) 0.0264(7) -0.0002(7) -0.0091(6) -0.0007(6) O12 0.0474(10) 0.0193(6) 0.0338(9) -0.0004(7) -0.0034(7) 0.0002(7) C2 0.0247(8) 0.0230(8) 0.0227(10) -0.0022(7) -0.0004(7) -0.0020(7) C3 0.0239(9) 0.0262(10) 0.0204(8) -0.0010(9) -0.0030(7) -0.0026(9) C4 0.0265(10) 0.0184(10) 0.0253(10) -0.0013(8) -0.0007(9) -0.0016(7) O41 0.0419(9) 0.0198(6) 0.0324(8) 0.0003(6) -0.0078(7) 0.0008(6) O42 0.0403(9) 0.0197(8) 0.0316(10) -0.0023(7) -0.0106(7) -0.0021(6) _geom_special_details ; All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 C1 O12 1.223(2) . ? C1 O11 1.303(3) . ? C1 C2 1.492(3) . ? O11 H11 0.978(19) . ? C2 C3 1.343(3) . ? C2 H2A 0.9500 . ? C3 C4 1.480(3) . ? C3 H3A 0.9500 . ? C4 O42 1.227(2) . ? C4 O41 1.307(3) . ? O41 H41 0.995(18) . ? 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 O12 C1 O11 119.12(19) . . ? O12 C1 C2 119.25(18) . . ? O11 C1 C2 121.62(15) . . ? C1 O11 H11 113(2) . . ? C3 C2 C1 131.54(18) . . ? C3 C2 H2A 114.2 . . ? C1 C2 H2A 114.2 . . ? C2 C3 C4 128.05(19) . . ? C2 C3 H3A 116.0 . . ? C4 C3 H3A 116.0 . . ? O42 C4 O41 122.68(19) . . ? O42 C4 C3 125.13(18) . . ? O41 C4 C3 112.18(17) . . ? C4 O41 H41 113.0(18) . . ? 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 O12 C1 C2 C3 176.6(2) . . . . ? O11 C1 C2 C3 -4.0(4) . . . . ? C1 C2 C3 C4 0.8(4) . . . . ? C2 C3 C4 O42 -2.2(3) . . . . ? C2 C3 C4 O41 178.1(2) . . . . ? _diffrn_measured_fraction_theta_max 0.992 _diffrn_reflns_theta_full 27.46 _diffrn_measured_fraction_theta_full 0.992 _refine_diff_density_max 0.185 _refine_diff_density_min -0.174 _refine_diff_density_rms 0.056