# Supplementary Material (ESI) for New Journal of Chemistry # This journal is © The Royal Society of Chemistry and # The Centre National de la Recherche Scientifique, 2000 # CCDC Number: 440/219 data_18dmn50K _publ_contact_author_name ; Chick C Wilson ; _publ_contact_author_address ; ISIS, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX ; _publ_contact_author_email 'C.C.Wilson@rl.ac.uk' _publ_contact_author_phone '+44 1235 445137' _publ_contact_author_fax '+44 1235 445720' _publ_requested_journal 'New Journal of Chemistry' _publ_requested_coeditor_name 'Prof J K M Sanders' _chemical_name_systematic ; 1,8-dimethylnaphthalene ; _chemical_name_common 1,8-dimethylnaphthalene _chemical_formula_sum 'C12 H12' _chemical_formula_weight 156.2 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_length_neutron _atom_type_scat_source "C" "C" 6.646 'International Tables Vol C Table 4.4.4.1' "H" "H" -3.739 'International Tables Vol C Table 4.4.4.1' _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 9.646(2) _cell_length_b 6.904(2) _cell_length_c 16.131(4) _cell_angle_alpha 90.00 _cell_angle_beta 124.43(2) _cell_angle_gamma 90.00 _cell_volume 886.1(4) _cell_formula_units_Z 4 _cell_measurement_temperature 50(1) _cell_measurement_reflns_used 25 _cell_measurement_theta_min ? _exptl_crystal_description 'thick plate' _exptl_crystal_colour 'pale yellow ' _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.5 _exptl_crystal_size_min 1.0 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.169 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 13.97 _exptl_absorpt_coefficient_mu '2.080, at 1 Angstrom' _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.41 _exptl_absorpt_correction_T_max 0.84 _exptl_absorpt_process_details ; The linear absorption coefficient is wavelength dependent and it is calculated as: mu = 1.08 + 1.00 * lambda [cm^-1] ; _exptl_special_details ; For peak integration a local UB matrix refined for each frame, using approximately 25 reflections. Hence _cell_measurement_reflns_used 25 For final cell dimensions an average of all local cells was performed and estimated standard uncertainties were obtained from the spread of the local observations Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. Instead, we can give values of _cell_measurement_sin(theta)/lambda_min 0.19 _cell_measurement_sin(theta)/lambda_max 0.75 The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.5-5.0 Angstroms, BUT the bulk of the diffraction information is obtained from wavelengths in the range 0.7-2.5 Angstroms. The data collection procedures on the SXD instrument used for the single crystal neutron data collection are most recently summarised in the Appendix to the following paper Wilson, C.C. (1997). J. Mol. Struct. 405, 207-217. ; _diffrn_ambient_temperature 50(1) _diffrn_radiation_wavelength 0.5-5.0 _diffrn_radiation_type neutron _diffrn_radiation_source 'ISIS spallation source' _diffrn_radiation_monochromator none _diffrn_measurement_device SXD _diffrn_measurement_method 'time-of-flight LAUE diffraction' _diffrn_reflns_number 2550 _diffrn_reflns_av_R_equivalents 0.065 _diffrn_reflns_av_sigmaI/netI 0.0632 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 16 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 12 _diffrn_reflns_limit_l_min -28 _diffrn_reflns_limit_l_max 18 _reflns_number_total 1033 _reflns_number_gt 1032 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution ? _computing_structure_refinement ' SHELXL-93 (Sheldrick, 1993)' _computing_molecular_graphics ' ORTEP (Johnson, 1994)' _computing_publication_material ? _refine_special_details ; The variable wavelength nature of the data collection procedure means that sensible values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given It is also difficult to estimate realistic values of maximum sin(theta)/lambda values for two reasons: (i) Different sin(theta)/lambda ranges are accessed in different parts of the detectors (ii) The nature of the data collection occasionally allows some reflections at very high sin(theta)/lambda to be observed even when no real attempt has been made to measure data in this region. However, we can attempt to estimate the sin(theta)/lambda limits as follows: _diffrn_reflns_sin(theta)/lambda_min 0.009 _diffrn_reflns_sin(theta)/lambda_max 0.64 Note also that reflections for which the standard profile fitting integration procedure fails are excluded from the data set, thus resulting in a high elimination rate of weak or "unobserved" peaks from the final data set. The extinction coefficient reported in _refine_ls_extinction_coef is in this case the refined value of the mosaic spread in units of 10^-4 rad^-1 The reference for the extinction method used is: Becker, P. & Coppens, P. (1974). Acta Cryst. A30, 129-148. 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 w=1/[\s^2^(Fo^2^)+(0.1423P)^2^+0.1472P] where P=(Fo^2^+2Fc^2^)/3' _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method 'Becker-Coppens Lorentzian model' _refine_ls_extinction_coef 0.130 _refine_ls_number_reflns 1033 _refine_ls_number_parameters 217 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0743 _refine_ls_R_factor_gt 0.0743 _refine_ls_wR_factor_ref 0.1823 _refine_ls_wR_factor_gt 0.1823 _refine_ls_goodness_of_fit_ref 1.097 _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_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group C1 C 0.2479(5) -0.0636(6) 0.4617(4) 0.0133(8) Uani 1 d . . . C2 C 0.1653(6) 0.0595(7) 0.4889(4) 0.0193(10) Uani 1 d . . . C3 C 0.0872(6) 0.2312(8) 0.4373(4) 0.0210(11) Uani 1 d . . . C4 C 0.0946(6) 0.2855(7) 0.3582(4) 0.0185(10) Uani 1 d . . . C10 C 0.1810(5) 0.1685(6) 0.3287(4) 0.0131(9) Uani 1 d . . . C9 C 0.2604(5) -0.0099(6) 0.3803(3) 0.0107(8) Uani 1 d . . . C8 C 0.3432(5) -0.1221(7) 0.3448(4) 0.0153(9) Uani 1 d . . . C7 C 0.3456(6) -0.0519(8) 0.2650(4) 0.0212(10) Uani 1 d . . . C6 C 0.2686(6) 0.1221(8) 0.2156(4) 0.0252(11) Uani 1 d . . . C5 C 0.1865(6) 0.2330(7) 0.2464(4) 0.0200(11) Uani 1 d . . . C11 C 0.3224(7) -0.2451(7) 0.5254(5) 0.0227(11) Uani 1 d . . . C12 C 0.4291(6) -0.3144(7) 0.3877(5) 0.0228(11) Uani 1 d . . . H2 H 0.1592(18) 0.0152(19) 0.5520(12) 0.047(3) Uani 1 d . . . H3 H 0.0210(16) 0.322(2) 0.4617(13) 0.049(4) Uani 1 d . . . H4 H 0.0355(13) 0.4197(16) 0.3179(10) 0.038(3) Uani 1 d . . . H5 H 0.1208(15) 0.3654(18) 0.2078(10) 0.040(3) Uani 1 d . . . H6 H 0.272(2) 0.172(2) 0.1526(13) 0.057(4) Uani 1 d . . . H7 H 0.4097(16) -0.1346(19) 0.2388(10) 0.040(3) Uani 1 d . . . H111 H 0.4587(15) -0.2549(19) 0.5650(12) 0.047(3) Uani 1 d . . . H112 H 0.2673(16) -0.3733(16) 0.4816(11) 0.046(3) Uani 1 d . . . H113 H 0.299(2) -0.242(2) 0.5842(14) 0.059(4) Uani 1 d . . . H121 H 0.5368(14) -0.3018(18) 0.4662(11) 0.044(3) Uani 1 d . . . H122 H 0.3433(17) -0.4232(16) 0.3828(13) 0.048(3) Uani 1 d . . . H123 H 0.473(2) -0.372(2) 0.3443(13) 0.056(4) Uani 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 0.0135(17) 0.013(2) 0.015(2) 0.0026(17) 0.0091(17) -0.0009(15) C2 0.0164(19) 0.024(2) 0.021(3) -0.005(2) 0.0122(19) -0.0016(18) C3 0.017(2) 0.026(3) 0.024(3) -0.006(2) 0.014(2) 0.0035(19) C4 0.014(2) 0.013(2) 0.022(3) 0.0010(18) 0.0059(19) 0.0049(16) C10 0.0072(16) 0.015(2) 0.013(2) 0.0013(16) 0.0031(16) 0.0007(14) C9 0.0074(16) 0.010(2) 0.014(2) 0.0004(15) 0.0051(16) -0.0011(13) C8 0.0145(19) 0.015(2) 0.018(3) -0.0015(18) 0.0102(18) -0.0013(17) C7 0.019(2) 0.028(3) 0.015(3) -0.002(2) 0.009(2) 0.0013(19) C6 0.023(2) 0.037(3) 0.018(3) 0.009(2) 0.013(2) 0.001(2) C5 0.018(2) 0.017(2) 0.019(3) 0.0078(18) 0.0071(19) -0.0003(17) C11 0.025(2) 0.018(3) 0.022(3) 0.007(2) 0.012(2) 0.0003(19) C12 0.022(2) 0.010(2) 0.034(3) 0.003(2) 0.015(2) 0.0043(18) H2 0.066(8) 0.046(7) 0.065(10) -0.006(7) 0.059(9) -0.006(6) H3 0.039(6) 0.051(7) 0.072(10) -0.009(7) 0.040(7) 0.010(6) H4 0.026(4) 0.030(6) 0.047(8) 0.016(5) 0.015(5) 0.017(4) H5 0.043(6) 0.036(6) 0.033(7) 0.024(5) 0.016(5) 0.012(5) H6 0.078(10) 0.072(9) 0.052(10) 0.027(8) 0.055(9) 0.007(8) H7 0.049(6) 0.055(7) 0.028(7) -0.005(6) 0.029(6) 0.002(6) H111 0.030(6) 0.047(8) 0.045(9) 0.012(6) 0.010(5) 0.004(5) H112 0.055(7) 0.020(5) 0.043(8) -0.002(5) 0.016(6) -0.018(5) H113 0.085(10) 0.060(9) 0.057(12) 0.024(8) 0.055(10) 0.022(8) H121 0.030(5) 0.038(6) 0.043(8) 0.007(6) 0.008(5) 0.013(5) H122 0.047(6) 0.026(5) 0.077(11) -0.006(6) 0.038(7) -0.013(5) H123 0.072(9) 0.051(8) 0.063(11) 0.009(7) 0.049(9) 0.026(7) _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 C2 1.395(6) . ? C1 C9 1.433(6) . ? C1 C11 1.520(7) . ? C2 C3 1.399(8) . ? C2 H2 1.097(14) . ? C3 C4 1.370(8) . ? C3 H3 1.113(12) . ? C4 C10 1.422(6) . ? C4 H4 1.089(12) . ? C10 C5 1.429(7) . ? C10 C9 1.441(6) . ? C9 C8 1.443(6) . ? C8 C7 1.388(7) . ? C8 C12 1.510(7) . ? C7 C6 1.401(8) . ? C7 H7 1.088(12) . ? C6 C5 1.380(8) . ? C6 H6 1.091(13) . ? C5 H5 1.086(12) . ? C11 H111 1.091(13) . ? C11 H112 1.068(14) . ? C11 H113 1.096(15) . ? C12 H121 1.096(16) . ? C12 H122 1.087(12) . ? C12 H123 1.076(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 C2 C1 C9 119.3(4) . . ? C2 C1 C11 115.2(4) . . ? C9 C1 C11 125.5(4) . . ? C1 C2 C3 122.7(5) . . ? C1 C2 H2 117.6(8) . . ? C3 C2 H2 119.7(8) . . ? C4 C3 C2 119.5(4) . . ? C4 C3 H3 121.2(10) . . ? C2 C3 H3 119.3(10) . . ? C3 C4 C10 120.3(4) . . ? C3 C4 H4 120.2(8) . . ? C10 C4 H4 119.5(8) . . ? C4 C10 C5 118.1(4) . . ? C4 C10 C9 120.9(4) . . ? C5 C10 C9 121.1(4) . . ? C1 C9 C10 117.2(4) . . ? C1 C9 C8 125.2(4) . . ? C10 C9 C8 117.6(4) . . ? C7 C8 C9 118.9(4) . . ? C7 C8 C12 116.1(4) . . ? C9 C8 C12 125.0(5) . . ? C8 C7 C6 123.1(4) . . ? C8 C7 H7 119.3(9) . . ? C6 C7 H7 117.6(8) . . ? C5 C6 C7 119.9(5) . . ? C5 C6 H6 119.2(9) . . ? C7 C6 H6 121.0(9) . . ? C6 C5 C10 119.5(4) . . ? C6 C5 H5 121.9(8) . . ? C10 C5 H5 118.6(8) . . ? C1 C11 H111 113.6(8) . . ? C1 C11 H112 111.6(9) . . ? H111 C11 H112 108.7(11) . . ? C1 C11 H113 108.5(9) . . ? H111 C11 H113 105.5(15) . . ? H112 C11 H113 108.7(13) . . ? C8 C12 H121 112.1(8) . . ? C8 C12 H122 112.1(8) . . ? H121 C12 H122 109.0(13) . . ? C8 C12 H123 110.0(9) . . ? H121 C12 H123 108.4(12) . . ? H122 C12 H123 104.9(13) . . ? _refine_diff_density_max 0.137 _refine_diff_density_min -0.162 _refine_diff_density_rms 0.030 data_18dmn150K _publ_contact_author_name ; Chick C Wilson ; _publ_contact_author_address ; ISIS, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX ; _publ_contact_author_email 'C.C.Wilson@rl.ac.uk' _publ_contact_author_phone '+44 1235 445137' _publ_contact_author_fax '+44 1235 445720' _publ_requested_journal 'New Journal of Chemistry' _publ_requested_coeditor_name 'Prof J K M Sanders' _chemical_name_systematic ; 1,8-dimethylnaphthalene ; _chemical_name_common 1,8-dimethylnaphthalene _chemical_formula_sum 'C12 H12' _chemical_formula_weight 156.2 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_length_neutron _atom_type_scat_source "C" "C" 6.646 'International Tables Vol C Table 4.4.4.1' "H" "H" -3.739 'International Tables Vol C Table 4.4.4.1' _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 9.725(2) _cell_length_b 6.938(2) _cell_length_c 16.147(4) _cell_angle_alpha 90.00 _cell_angle_beta 124.40(2) _cell_angle_gamma 90.00 _cell_volume 898.9(4) _cell_formula_units_Z 4 _cell_measurement_temperature 150(1) _cell_measurement_reflns_used 25 _cell_measurement_theta_min ? _exptl_crystal_description 'thick plate' _exptl_crystal_colour 'pale yellow ' _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.5 _exptl_crystal_size_min 1.0 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.153 _exptl_crystal_density_method ' not measured' _exptl_crystal_F_000 13.97 _exptl_absorpt_coefficient_mu ' 2.080, at 1 Angstrom' _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.41 _exptl_absorpt_correction_T_max 0.84 _exptl_absorpt_process_details ; The linear absorption coefficient is wavelength dependent and it is calculated as: mu = 1.08 + 1.00 * lambda [cm^-1] ; _exptl_special_details ; For peak integration a local UB matrix refined for each frame, using approximately 25 reflections. Hence _cell_measurement_reflns_used 25 For final cell dimensions an average of all local cells was performed and estimated standard uncertainties were obtained from the spread of the local observations Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. Instead, we can give values of _cell_measurement_sin(theta)/lambda_min 0.19 _cell_measurement_sin(theta)/lambda_max 0.71 The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.5-5.0 Angstroms, BUT the bulk of the diffraction information is obtained from wavelengths in the range 0.7-2.5 Angstroms. The data collection procedures on the SXD instrument used for the single crystal neutron data collection are most recently summarised in the Appendix to the following paper Wilson, C.C. (1997). J. Mol. Struct. 405, 207-217. ; _diffrn_ambient_temperature 150(1) _diffrn_radiation_wavelength 0.5-5.0 _diffrn_radiation_type neutron _diffrn_radiation_source ' ISIS spallation source' _diffrn_radiation_monochromator none _diffrn_measurement_device SXD _diffrn_measurement_method ' time-of-flight LAUE diffraction' _diffrn_reflns_number 1947 _diffrn_reflns_av_R_equivalents 0.077 _diffrn_reflns_av_sigmaI/netI 0.0553 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 15 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 10 _diffrn_reflns_limit_l_min -22 _diffrn_reflns_limit_l_max 16 _reflns_number_total 751 _reflns_number_gt 751 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution ? _computing_structure_refinement ' SHELXL-93 (Sheldrick, 1993)' _computing_molecular_graphics ' ORTEP (Johnson, 1994)' _computing_publication_material ? _refine_special_details ; The variable wavelength nature of the data collection procedure means that sensible values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given It is also difficult to estimate realistic values of maximum sin(theta)/lambda values for two reasons: (i) Different sin(theta)/lambda ranges are accessed in different parts of the detectors (ii) The nature of the data collection occasionally allows some reflections at very high sin(theta)/lambda to be observed even when no real attempt has been made to measure data in this region. However, we can attempt to estimate the sin(theta)/lambda limits as follows: _diffrn_reflns_sin(theta)/lambda_min 0.016 _diffrn_reflns_sin(theta)/lambda_max 0.48 Note also that reflections for which the standard profile fitting integration procedure fails are excluded from the data set, thus resulting in a high elimination rate of weak or "unobserved" peaks from the final data set. The extinction coefficient reported in _refine_ls_extinction_coef is in this case the refined value of the mosaic spread in units of 10^-4 rad^-1 The reference for the extinction method used is: Becker, P. & Coppens, P. (1974). Acta Cryst. A30, 129-148. 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 w=1/[\s^2^(Fo^2^)+(0.1644P)^2^+0.0842P] where P=(Fo^2^+2Fc^2^)/3' _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method ' Becker-Coppens Lorentzian model' _refine_ls_extinction_coef 0.130 _refine_ls_number_reflns 751 _refine_ls_number_parameters 217 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0736 _refine_ls_R_factor_gt 0.0736 _refine_ls_wR_factor_ref 0.1793 _refine_ls_wR_factor_gt 0.1793 _refine_ls_goodness_of_fit_ref 1.074 _refine_ls_restrained_S_all 1.074 _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_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group C1 C 0.2483(6) -0.0622(8) 0.4612(4) 0.0229(13) Uani 1 d . . . C2 C 0.1661(7) 0.0597(10) 0.4878(6) 0.0341(17) Uani 1 d . . . C3 C 0.0892(7) 0.2286(11) 0.4367(6) 0.0369(18) Uani 1 d . . . C4 C 0.0953(7) 0.2824(10) 0.3572(6) 0.0338(16) Uani 1 d . . . C10 C 0.1822(7) 0.1670(7) 0.3277(5) 0.0236(13) Uani 1 d . . . C9 C 0.2607(6) -0.0106(8) 0.3802(4) 0.0175(12) Uani 1 d . . . C8 C 0.3429(6) -0.1224(8) 0.3437(5) 0.0243(13) Uani 1 d . . . C7 C 0.3447(8) -0.0507(10) 0.2647(6) 0.0359(16) Uani 1 d . . . C6 C 0.2689(9) 0.1206(12) 0.2153(6) 0.046(2) Uani 1 d . . . C5 C 0.1866(8) 0.2307(11) 0.2457(6) 0.0391(19) Uani 1 d . . . C11 C 0.3230(10) -0.2458(11) 0.5251(8) 0.0400(18) Uani 1 d . . . C12 C 0.4290(9) -0.3127(10) 0.3872(7) 0.039(2) Uani 1 d . . . H2 H 0.157(2) 0.013(2) 0.5491(14) 0.064(5) Uani 1 d . . . H3 H 0.018(2) 0.315(2) 0.4579(16) 0.069(5) Uani 1 d . . . H4 H 0.0373(16) 0.416(2) 0.3164(13) 0.061(5) Uani 1 d . . . H5 H 0.1256(17) 0.364(2) 0.2103(13) 0.061(4) Uani 1 d . . . H6 H 0.277(3) 0.171(3) 0.1554(16) 0.088(7) Uani 1 d . . . H7 H 0.406(2) -0.135(3) 0.2370(12) 0.064(5) Uani 1 d . . . H111 H 0.455(2) -0.253(3) 0.5623(18) 0.078(7) Uani 1 d . . . H112 H 0.269(2) -0.371(2) 0.4802(16) 0.067(5) Uani 1 d . . . H113 H 0.295(3) -0.246(3) 0.5813(18) 0.087(7) Uani 1 d . . . H121 H 0.5320(19) -0.298(2) 0.4633(15) 0.059(4) Uani 1 d . . . H122 H 0.3455(19) -0.4230(19) 0.3825(14) 0.059(4) Uani 1 d . . . H123 H 0.475(2) -0.372(3) 0.3474(16) 0.075(5) Uani 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 0.023(2) 0.023(3) 0.025(3) 0.000(2) 0.015(2) -0.003(2) C2 0.031(3) 0.040(4) 0.037(5) -0.003(3) 0.022(4) -0.002(3) C3 0.024(3) 0.048(5) 0.037(5) -0.010(3) 0.017(3) 0.004(3) C4 0.023(3) 0.026(3) 0.046(5) -0.001(3) 0.016(3) 0.006(3) C10 0.024(2) 0.017(3) 0.028(4) 0.002(2) 0.013(2) 0.004(2) C9 0.015(2) 0.020(3) 0.015(3) -0.002(2) 0.007(2) -0.005(2) C8 0.018(2) 0.025(3) 0.027(3) -0.011(3) 0.011(2) -0.003(2) C7 0.038(3) 0.047(4) 0.030(4) -0.008(3) 0.023(3) -0.002(3) C6 0.052(4) 0.062(5) 0.031(5) 0.001(4) 0.028(4) -0.014(4) C5 0.032(3) 0.034(4) 0.042(5) 0.020(3) 0.015(3) 0.000(3) C11 0.044(4) 0.034(5) 0.037(5) 0.010(4) 0.020(4) 0.002(3) C12 0.038(4) 0.020(4) 0.066(7) -0.004(4) 0.032(5) 0.002(3) H2 0.076(10) 0.082(11) 0.080(13) 0.000(10) 0.071(11) -0.002(10) H3 0.064(9) 0.069(10) 0.092(14) -0.002(10) 0.056(10) 0.024(8) H4 0.042(7) 0.048(9) 0.075(13) 0.018(8) 0.024(8) 0.025(6) H5 0.054(8) 0.058(9) 0.047(9) 0.034(8) 0.013(6) 0.011(7) H6 0.125(15) 0.113(15) 0.083(15) 0.027(13) 0.094(15) 0.009(13) H7 0.074(9) 0.092(12) 0.051(11) -0.022(9) 0.052(10) -0.012(10) H111 0.058(10) 0.073(12) 0.10(2) 0.018(11) 0.042(12) 0.007(9) H112 0.081(10) 0.032(8) 0.080(14) -0.010(9) 0.041(10) -0.016(8) H113 0.119(16) 0.090(15) 0.089(19) 0.048(13) 0.080(16) 0.036(12) H121 0.046(8) 0.056(9) 0.065(13) 0.019(9) 0.025(9) 0.023(8) H122 0.061(8) 0.033(8) 0.085(14) -0.002(7) 0.042(10) -0.012(7) H123 0.077(11) 0.075(11) 0.092(16) 0.007(11) 0.061(12) 0.024(10) _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 C2 1.388(8) . ? C1 C9 1.426(8) . ? C1 C11 1.539(10) . ? C2 C3 1.384(10) . ? C2 H2 1.089(18) . ? C3 C4 1.370(11) . ? C3 H3 1.107(15) . ? C4 C10 1.428(8) . ? C4 H4 1.089(18) . ? C10 C5 1.418(9) . ? C10 C9 1.445(7) . ? C9 C8 1.456(8) . ? C8 C7 1.379(9) . ? C8 C12 1.508(10) . ? C7 C6 1.388(11) . ? C7 H7 1.100(16) . ? C6 C5 1.383(11) . ? C6 H6 1.076(16) . ? C5 H5 1.075(18) . ? C11 H111 1.07(2) . ? C11 H112 1.06(2) . ? C11 H113 1.08(2) . ? C12 H121 1.06(2) . ? C12 H122 1.086(17) . ? C12 H123 1.05(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 C2 C1 C9 119.6(5) . . ? C2 C1 C11 115.7(6) . . ? C9 C1 C11 124.8(5) . . ? C3 C2 C1 122.9(7) . . ? C3 C2 H2 120.2(10) . . ? C1 C2 H2 116.9(10) . . ? C4 C3 C2 119.7(6) . . ? C4 C3 H3 120.6(13) . . ? C2 C3 H3 119.6(12) . . ? C3 C4 C10 120.5(6) . . ? C3 C4 H4 121.1(10) . . ? C10 C4 H4 118.4(11) . . ? C5 C10 C4 118.2(6) . . ? C5 C10 C9 122.0(5) . . ? C4 C10 C9 119.9(6) . . ? C1 C9 C10 117.5(5) . . ? C1 C9 C8 126.0(5) . . ? C10 C9 C8 116.5(5) . . ? C7 C8 C9 118.6(5) . . ? C7 C8 C12 116.9(6) . . ? C9 C8 C12 124.5(6) . . ? C8 C7 C6 124.1(6) . . ? C8 C7 H7 118.7(11) . . ? C6 C7 H7 117.2(11) . . ? C5 C6 C7 119.6(6) . . ? C5 C6 H6 119.5(13) . . ? C7 C6 H6 120.8(12) . . ? C6 C5 C10 119.2(6) . . ? C6 C5 H5 122.9(11) . . ? C10 C5 H5 117.9(11) . . ? C1 C11 H111 112.1(11) . . ? C1 C11 H112 110.8(13) . . ? H111 C11 H112 108.6(16) . . ? C1 C11 H113 108.3(11) . . ? H111 C11 H113 108.7(19) . . ? H112 C11 H113 108.2(18) . . ? C8 C12 H121 111.5(10) . . ? C8 C12 H122 112.8(10) . . ? H121 C12 H122 109.1(15) . . ? C8 C12 H123 111.9(13) . . ? H121 C12 H123 107.1(14) . . ? H122 C12 H123 103.9(15) . . ? _refine_diff_density_max 0.096 _refine_diff_density_min -0.093 _refine_diff_density_rms 0.023 data_18dmn200K _publ_contact_author_name ; Chick C Wilson ; _publ_contact_author_address ; ISIS, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX ; _publ_contact_author_email 'C.C.Wilson@rl.ac.uk' _publ_contact_author_phone '+44 1235 445137' _publ_contact_author_fax '+44 1235 445720' _publ_requested_journal 'New Journal of Chemistry' _publ_requested_coeditor_name 'Prof J K M Sanders' _chemical_name_systematic ; 1,8-dimethylnaphthalene ; _chemical_name_common 1,8-dimethylnaphthalene _chemical_formula_sum 'C12 H12' _chemical_formula_weight 156.2 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_length_neutron _atom_type_scat_source "C" "C" 6.646 'International Tables Vol C Table 4.4.4.1' "H" "H" -3.739 'International Tables Vol C Table 4.4.4.1' _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 9.773(2) _cell_length_b 6.955(2) _cell_length_c 16.158(5) _cell_angle_alpha 90.00 _cell_angle_beta 124.36(2) _cell_angle_gamma 90.00 _cell_volume 906.6(4) _cell_formula_units_Z 4 _cell_measurement_temperature 200(1) _cell_measurement_reflns_used 25 _cell_measurement_theta_min ? _exptl_crystal_description 'thick plate' _exptl_crystal_colour 'pale yellow ' _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.5 _exptl_crystal_size_min 1.0 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.143 _exptl_crystal_density_method ' not measured' _exptl_crystal_F_000 13.97 _exptl_absorpt_coefficient_mu '2.080, at 1 Angstrom' _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.41 _exptl_absorpt_correction_T_max 0.84 _exptl_absorpt_process_details ; The linear absorption coefficient is wavelength dependent and it is calculated as: mu = 1.08 + 1.00 * lambda [cm^-1] ; _exptl_special_details ; For peak integration a local UB matrix refined for each frame, using approximately 25 reflections. Hence _cell_measurement_reflns_used 25 For final cell dimensions an average of all local cells was performed and estimated standard uncertainties were obtained from the spread of the local observations Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. Instead, we can give values of _cell_measurement_sin(theta)/lambda_min 0.18 _cell_measurement_sin(theta)/lambda_max 0.64 The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.5-5.0 Angstroms, BUT the bulk of the diffraction information is obtained from wavelengths in the range 0.7-2.5 Angstroms. The data collection procedures on the SXD instrument used for the single crystal neutron data collection are most recently summarised in the Appendix to the following paper Wilson, C.C. (1997). J. Mol. Struct. 405, 207-217. ; _diffrn_ambient_temperature 200(1) _diffrn_radiation_wavelength 0.5-5.0 _diffrn_radiation_type neutron _diffrn_radiation_source 'ISIS spallation source' _diffrn_radiation_monochromator none _diffrn_measurement_device SXD _diffrn_measurement_method 'time-of-flight LAUE diffraction' _diffrn_reflns_number 1566 _diffrn_reflns_av_R_equivalents 0.091 _diffrn_reflns_av_sigmaI/netI 0.0534 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 13 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 9 _diffrn_reflns_limit_l_min -22 _diffrn_reflns_limit_l_max 13 _reflns_number_total 596 _reflns_number_gt 596 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution ? _computing_structure_refinement ' SHELXL-93 (Sheldrick, 1993)' _computing_molecular_graphics ' ORTEP (Johnson, 1994)' _computing_publication_material ? _refine_special_details ; The variable wavelength nature of the data collection procedure means that sensible values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given It is also difficult to estimate realistic values of maximum sin(theta)/lambda values for two reasons: (i) Different sin(theta)/lambda ranges are accessed in different parts of the detectors (ii) The nature of the data collection occasionally allows some reflections at very high sin(theta)/lambda to be observed even when no real attempt has been made to measure data in this region. However, we can attempt to estimate the sin(theta)/lambda limits as follows: _diffrn_reflns_sin(theta)/lambda_min 0.009 _diffrn_reflns_sin(theta)/lambda_max 0.40 Note also that reflections for which the standard profile fitting integration procedure fails are excluded from the data set, thus resulting in a high elimination rate of weak or "unobserved" peaks from the final data set. The extinction coefficient reported in _refine_ls_extinction_coef is in this case the refined value of the mosaic spread in units of 10^-4 rad^-1 The reference for the extinction method used is: Becker, P. & Coppens, P. (1974). Acta Cryst. A30, 129-148. 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 w=1/[\s^2^(Fo^2^)+(0.1568P)^2^+0.1603P] where P=(Fo^2^+2Fc^2^)/3' _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method ' Becker-Coppens Lorentzian model' _refine_ls_extinction_coef 0.130 _refine_ls_number_reflns 596 _refine_ls_number_parameters 217 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0766 _refine_ls_R_factor_gt 0.0766 _refine_ls_wR_factor_ref 0.1885 _refine_ls_wR_factor_gt 0.1885 _refine_ls_goodness_of_fit_ref 1.132 _refine_ls_restrained_S_all 1.132 _refine_ls_shift/su_max 0.009 _refine_ls_shift/su_mean 0.002 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_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group C1 C 0.2488(9) -0.0629(13) 0.4609(7) 0.034(2) Uani 1 d . . . C2 C 0.1649(11) 0.0585(15) 0.4862(8) 0.042(3) Uani 1 d . . . C3 C 0.0877(10) 0.2268(15) 0.4344(8) 0.044(3) Uani 1 d . . . C4 C 0.0969(11) 0.2828(15) 0.3563(9) 0.045(3) Uani 1 d . . . C10 C 0.1832(9) 0.1656(11) 0.3289(7) 0.031(2) Uani 1 d . . . C9 C 0.2595(9) -0.0115(11) 0.3784(7) 0.031(2) Uani 1 d . . . C8 C 0.3415(9) -0.1227(11) 0.3433(7) 0.032(2) Uani 1 d . . . C7 C 0.3441(12) -0.0535(16) 0.2650(9) 0.048(3) Uani 1 d . . . C6 C 0.2685(15) 0.1195(18) 0.2146(10) 0.062(3) Uani 1 d . . . C5 C 0.1864(12) 0.2277(17) 0.2443(9) 0.051(3) Uani 1 d . . . C11 C 0.3216(16) -0.2440(16) 0.5256(12) 0.053(3) Uani 1 d . . . C12 C 0.4284(16) -0.3107(16) 0.3862(12) 0.053(3) Uani 1 d . . . H2 H 0.157(3) 0.010(3) 0.549(2) 0.088(8) Uani 1 d . . . H3 H 0.020(3) 0.317(4) 0.458(2) 0.087(8) Uani 1 d . . . H4 H 0.040(2) 0.413(3) 0.319(2) 0.078(8) Uani 1 d . . . H5 H 0.126(3) 0.364(4) 0.209(2) 0.081(8) Uani 1 d . . . H6 H 0.276(6) 0.173(5) 0.156(3) 0.129(14) Uani 1 d . . . H7 H 0.406(3) -0.140(4) 0.2359(19) 0.078(7) Uani 1 d . . . H111 H 0.455(4) -0.253(4) 0.563(3) 0.097(10) Uani 1 d . . . H112 H 0.267(3) -0.370(3) 0.478(2) 0.083(8) Uani 1 d . . . H113 H 0.295(5) -0.250(4) 0.578(3) 0.100(11) Uani 1 d . . . H121 H 0.532(3) -0.294(3) 0.464(3) 0.073(7) Uani 1 d . . . H122 H 0.347(3) -0.426(3) 0.381(2) 0.089(9) Uani 1 d . . . H123 H 0.474(4) -0.371(4) 0.347(3) 0.102(10) Uani 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 0.035(4) 0.037(5) 0.033(6) 0.004(4) 0.020(4) -0.005(3) C2 0.037(5) 0.055(6) 0.048(7) -0.007(5) 0.031(5) -0.006(5) C3 0.025(4) 0.054(6) 0.049(7) -0.022(6) 0.018(4) 0.002(4) C4 0.031(5) 0.035(6) 0.058(8) -0.001(5) 0.019(5) 0.004(4) C10 0.024(4) 0.029(5) 0.028(5) 0.006(4) 0.008(3) 0.007(3) C9 0.024(4) 0.025(4) 0.041(6) 0.006(4) 0.017(4) 0.002(3) C8 0.026(4) 0.038(5) 0.030(5) -0.020(4) 0.013(4) -0.010(4) C7 0.042(5) 0.064(7) 0.037(7) -0.009(6) 0.023(5) -0.002(5) C6 0.069(7) 0.080(9) 0.058(10) -0.005(8) 0.049(8) -0.011(7) C5 0.044(5) 0.051(7) 0.043(7) 0.027(5) 0.015(5) 0.000(5) C11 0.061(7) 0.043(7) 0.054(9) 0.005(6) 0.031(6) 0.002(6) C12 0.052(7) 0.032(6) 0.083(11) 0.012(6) 0.044(8) 0.009(5) H2 0.109(18) 0.092(16) 0.11(3) 0.000(17) 0.09(2) -0.001(16) H3 0.064(13) 0.105(16) 0.10(2) -0.025(17) 0.048(15) 0.021(13) H4 0.040(10) 0.053(13) 0.12(2) 0.012(13) 0.034(13) 0.016(9) H5 0.073(14) 0.073(15) 0.11(2) 0.045(16) 0.054(16) 0.021(14) H6 0.21(4) 0.13(2) 0.12(3) 0.05(2) 0.14(3) 0.01(3) H7 0.079(14) 0.116(19) 0.070(18) -0.016(15) 0.062(15) -0.005(14) H111 0.072(17) 0.089(18) 0.13(3) 0.001(16) 0.057(19) 0.005(13) H112 0.112(17) 0.015(9) 0.08(2) 0.006(11) 0.033(15) -0.011(11) H113 0.15(3) 0.10(2) 0.09(3) 0.046(17) 0.09(3) 0.032(19) H121 0.049(12) 0.062(13) 0.09(2) 0.001(14) 0.032(15) 0.007(10) H122 0.078(14) 0.041(11) 0.15(3) -0.012(14) 0.067(18) -0.021(11) H123 0.11(2) 0.084(18) 0.14(3) 0.012(18) 0.08(2) 0.040(16) _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 C2 1.389(12) . ? C1 C9 1.440(12) . ? C1 C11 1.532(15) . ? C2 C3 1.388(15) . ? C2 H2 1.11(3) . ? C3 C4 1.371(15) . ? C3 H3 1.13(2) . ? C4 C10 1.412(13) . ? C4 H4 1.06(3) . ? C10 C9 1.428(11) . ? C10 C5 1.451(14) . ? C9 C8 1.441(12) . ? C8 C7 1.367(15) . ? C8 C12 1.499(14) . ? C7 C6 1.406(17) . ? C7 H7 1.13(3) . ? C6 C5 1.369(16) . ? C6 H6 1.05(3) . ? C5 H5 1.09(3) . ? C11 H111 1.09(4) . ? C11 H112 1.08(3) . ? C11 H113 1.01(4) . ? C12 H121 1.09(4) . ? C12 H122 1.10(3) . ? C12 H123 1.04(4) . ? 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 C2 C1 C9 119.0(8) . . ? C2 C1 C11 115.1(9) . . ? C9 C1 C11 125.9(8) . . ? C3 C2 C1 123.1(9) . . ? C3 C2 H2 120.8(14) . . ? C1 C2 H2 116.1(15) . . ? C4 C3 C2 119.9(8) . . ? C4 C3 H3 120.8(19) . . ? C2 C3 H3 119.3(19) . . ? C3 C4 C10 119.1(9) . . ? C3 C4 H4 118.5(17) . . ? C10 C4 H4 122.4(17) . . ? C4 C10 C9 122.5(9) . . ? C4 C10 C5 117.3(8) . . ? C9 C10 C5 120.2(8) . . ? C10 C9 C1 116.4(7) . . ? C10 C9 C8 118.2(8) . . ? C1 C9 C8 125.4(7) . . ? C7 C8 C9 118.7(8) . . ? C7 C8 C12 115.7(9) . . ? C9 C8 C12 125.6(10) . . ? C8 C7 C6 124.0(9) . . ? C8 C7 H7 119.4(17) . . ? C6 C7 H7 116.6(18) . . ? C5 C6 C7 119.2(10) . . ? C5 C6 H6 118(2) . . ? C7 C6 H6 123(2) . . ? C6 C5 C10 119.6(10) . . ? C6 C5 H5 123.2(16) . . ? C10 C5 H5 117.1(16) . . ? C1 C11 H111 112.1(18) . . ? C1 C11 H112 109.3(18) . . ? H111 C11 H112 108(2) . . ? C1 C11 H113 111.2(18) . . ? H111 C11 H113 109(3) . . ? H112 C11 H113 107(3) . . ? C8 C12 H121 111.1(14) . . ? C8 C12 H122 113.7(16) . . ? H121 C12 H122 109(2) . . ? C8 C12 H123 114(2) . . ? H121 C12 H123 108(2) . . ? H122 C12 H123 102(2) . . ? _refine_diff_density_max 0.096 _refine_diff_density_min -0.088 _refine_diff_density_rms 0.020 data_18dmn100K _publ_contact_author_name ; Chick C Wilson ; _publ_contact_author_address ; ISIS, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX ; _publ_contact_author_email 'C.C.Wilson@rl.ac.uk' _publ_contact_author_phone '+44 1235 445137' _publ_contact_author_fax '+44 1235 445720' _publ_requested_journal 'New Journal of Chemistry' _publ_requested_coeditor_name 'Prof J K M Sanders' _chemical_name_systematic ; 1,8-dimethylnaphthalene ; _chemical_name_common 1,8-dimethylnaphthalene _chemical_formula_sum 'C12 H12' _chemical_formula_weight 156.2 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_length_neutron _atom_type_scat_source "C" "C" 6.646 'International Tables Vol C Table 4.4.4.1' "H" "H" -3.739 'International Tables Vol C Table 4.4.4.1' _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 9.678(2) _cell_length_b 6.917(2) _cell_length_c 16.141(4) _cell_angle_alpha 90.00 _cell_angle_beta 124.39(2) _cell_angle_gamma 90.00 _cell_volume 891.7(4) _cell_formula_units_Z 4 _cell_measurement_temperature 100(1) _cell_measurement_reflns_used 25 _cell_measurement_theta_min ? _exptl_crystal_description 'thick plate' _exptl_crystal_colour 'pale yellow' _exptl_crystal_size_max 2.5 _exptl_crystal_size_mid 2.5 _exptl_crystal_size_min 1.0 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.162 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 13.97 _exptl_absorpt_coefficient_mu '2.080, at 1 Angstrom' _exptl_absorpt_correction_type empirical _exptl_absorpt_correction_T_min 0.41 _exptl_absorpt_correction_T_max 0.84 _exptl_absorpt_process_details ; The linear absorption coefficient is wavelength dependent and it is calculated as: mu = 1.08 + 1.00 * lambda [cm^-1] ; _exptl_special_details ; For peak integration a local UB matrix refined for each frame, using approximately 25 reflections. Hence _cell_measurement_reflns_used 25 For final cell dimensions an average of all local cells was performed and estimated standard uncertainties were obtained from the spread of the local observations Because of the nature of the experiment, it is not possible to give values of theta_min and theta_max for the cell determination. Instead, we can give values of _cell_measurement_sin(theta)/lambda_min 0.19 _cell_measurement_sin(theta)/lambda_max 0.73 The same applies for the wavelength used for the experiment. The range of wavelengths used was 0.5-5.0 Angstroms, BUT the bulk of the diffraction information is obtained from wavelengths in the range 0.7-2.5 Angstroms. The data collection procedures on the SXD instrument used for the single crystal neutron data collection are most recently summarised in the Appendix to the following paper Wilson, C.C. (1997). J. Mol. Struct. 405, 207-217. ; _diffrn_ambient_temperature 100(1) _diffrn_radiation_wavelength 0.5-5.0 _diffrn_radiation_type neutron _diffrn_radiation_source 'ISIS spallation source' _diffrn_radiation_monochromator none _diffrn_measurement_device SXD _diffrn_measurement_method 'time-of-flight LAUE diffraction' _diffrn_reflns_number 2788 _diffrn_reflns_av_R_equivalents 0.062 _diffrn_reflns_av_sigmaI/netI 0.0446 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_h_max 16 _diffrn_reflns_limit_k_min 0 _diffrn_reflns_limit_k_max 12 _diffrn_reflns_limit_l_min -28 _diffrn_reflns_limit_l_max 18 _reflns_number_total 1297 _reflns_number_gt 1297 _reflns_threshold_expression >2sigma(I) _computing_data_collection ? _computing_cell_refinement ? _computing_data_reduction ? _computing_structure_solution ? _computing_structure_refinement ' SHELXL-93 (Sheldrick, 1993)' _computing_molecular_graphics ' ORTEP (Johnson, 1994)' _computing_publication_material ? _refine_special_details ; The variable wavelength nature of the data collection procedure means that sensible values of _diffrn_reflns_theta_min & _diffrn_reflns_theta_max cannot be given It is also difficult to estimate realistic values of maximum sin(theta)/lambda values for two reasons: (i) Different sin(theta)/lambda ranges are accessed in different parts of the detectors (ii) The nature of the data collection occasionally allows some reflections at very high sin(theta)/lambda to be observed even when no real attempt has been made to measure data in this region. However, we can attempt to estimate the sin(theta)/lambda limits as follows: _diffrn_reflns_sin(theta)/lambda_min 0.009 _diffrn_reflns_sin(theta)/lambda_max 0.62 Note also that reflections for which the standard profile fitting integration procedure fails are excluded from the data set, thus resulting in a high elimination rate of weak or "unobserved" peaks from the final data set. The extinction coefficient reported in _refine_ls_extinction_coef is in this case the refined value of the mosaic spread in units of 10^-4 rad^-1 The reference for the extinction method used is: Becker, P. & Coppens, P. (1974). Acta Cryst. A30, 129-148. 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 w=1/[\s^2^(Fo^2^)+(0.1216P)^2^+0.3666P] where P=(Fo^2^+2Fc^2^)/3' _refine_ls_hydrogen_treatment refall _refine_ls_extinction_method 'Becker-Coppens Lorentzian model' _refine_ls_extinction_coef 0.130 _refine_ls_number_reflns 1297 _refine_ls_number_parameters 217 _refine_ls_number_restraints 0 _refine_ls_R_factor_all 0.0933 _refine_ls_R_factor_gt 0.0933 _refine_ls_wR_factor_ref 0.2226 _refine_ls_wR_factor_gt 0.2226 _refine_ls_goodness_of_fit_ref 1.190 _refine_ls_restrained_S_all 1.190 _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_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group C1 C 0.2491(5) -0.0639(6) 0.4621(4) 0.0172(8) Uani 1 d . . . C2 C 0.1663(6) 0.0594(8) 0.4891(4) 0.0241(10) Uani 1 d . . . C3 C 0.0862(6) 0.2309(8) 0.4368(4) 0.0285(11) Uani 1 d . . . C4 C 0.0953(5) 0.2847(7) 0.3580(4) 0.0233(10) Uani 1 d . . . C10 C 0.1813(5) 0.1676(6) 0.3284(3) 0.0172(8) Uani 1 d . . . C9 C 0.2598(5) -0.0106(6) 0.3799(3) 0.0142(8) Uani 1 d . . . C8 C 0.3427(5) -0.1216(7) 0.3442(4) 0.0193(8) Uani 1 d . . . C7 C 0.3454(6) -0.0514(9) 0.2649(4) 0.0270(10) Uani 1 d . . . C6 C 0.2693(7) 0.1225(10) 0.2159(5) 0.0342(12) Uani 1 d . . . C5 C 0.1872(6) 0.2316(8) 0.2467(4) 0.0263(10) Uani 1 d . . . C11 C 0.3216(7) -0.2453(8) 0.5247(5) 0.0290(10) Uani 1 d . . . C12 C 0.4285(7) -0.3141(8) 0.3876(5) 0.0293(11) Uani 1 d . . . H2 H 0.1607(18) 0.015(2) 0.5524(12) 0.052(3) Uani 1 d . . . H3 H 0.0187(18) 0.319(2) 0.4589(14) 0.061(4) Uani 1 d . . . H4 H 0.0345(14) 0.4162(19) 0.3163(10) 0.048(3) Uani 1 d . . . H5 H 0.1200(15) 0.3644(19) 0.2074(10) 0.049(3) Uani 1 d . . . H6 H 0.273(2) 0.171(3) 0.1534(13) 0.066(4) Uani 1 d . . . H7 H 0.4105(17) -0.136(2) 0.2401(10) 0.048(3) Uani 1 d . . . H111 H 0.4580(14) -0.2529(19) 0.5632(12) 0.052(3) Uani 1 d . . . H112 H 0.2671(18) -0.3771(18) 0.4814(12) 0.053(3) Uani 1 d . . . H113 H 0.292(3) -0.248(3) 0.5798(15) 0.072(5) Uani 1 d . . . H121 H 0.5355(15) -0.301(2) 0.4652(11) 0.051(3) Uani 1 d . . . H122 H 0.3446(18) -0.4217(19) 0.3826(14) 0.056(4) Uani 1 d . . . H123 H 0.474(2) -0.372(2) 0.3449(14) 0.062(4) Uani 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 0.0162(16) 0.0166(19) 0.020(2) 0.0014(15) 0.0105(15) -0.0016(14) C2 0.0191(18) 0.031(2) 0.025(3) -0.0030(19) 0.0145(18) -0.0018(17) C3 0.0191(18) 0.035(3) 0.032(3) -0.006(2) 0.0151(19) 0.0041(18) C4 0.0138(17) 0.021(2) 0.025(3) 0.0003(17) 0.0055(16) 0.0060(15) C10 0.0121(15) 0.0140(19) 0.019(2) 0.0037(15) 0.0045(14) 0.0012(13) C9 0.0111(15) 0.015(2) 0.015(2) 0.0022(14) 0.0063(14) -0.0007(12) C8 0.0181(17) 0.0168(19) 0.022(2) -0.0038(15) 0.0109(16) -0.0019(14) C7 0.027(2) 0.039(3) 0.020(3) -0.006(2) 0.016(2) -0.005(2) C6 0.032(2) 0.049(3) 0.025(3) 0.002(2) 0.019(2) -0.006(2) C5 0.0215(19) 0.027(3) 0.022(3) 0.0076(18) 0.0071(17) 0.0001(17) C11 0.033(2) 0.023(2) 0.028(3) 0.0064(19) 0.015(2) -0.0008(19) C12 0.028(2) 0.021(2) 0.039(3) -0.001(2) 0.018(2) 0.0046(18) H2 0.061(7) 0.061(8) 0.067(9) 0.004(7) 0.056(8) 0.004(6) H3 0.050(7) 0.068(9) 0.082(11) -0.011(8) 0.047(8) 0.013(6) H4 0.029(5) 0.043(7) 0.051(7) 0.012(5) 0.009(4) 0.016(4) H5 0.044(6) 0.044(7) 0.041(7) 0.027(5) 0.014(5) 0.002(5) H6 0.085(10) 0.084(11) 0.059(10) 0.023(8) 0.059(9) 0.012(9) H7 0.055(7) 0.067(8) 0.040(7) -0.003(6) 0.038(6) 0.009(6) H111 0.026(5) 0.048(7) 0.059(9) 0.019(6) 0.010(5) 0.006(4) H112 0.060(7) 0.022(5) 0.066(9) 0.001(5) 0.028(7) -0.011(5) H113 0.105(13) 0.072(11) 0.072(13) 0.031(9) 0.070(12) 0.015(10) H121 0.033(5) 0.048(7) 0.049(8) 0.011(6) 0.009(5) 0.014(5) H122 0.055(7) 0.032(6) 0.085(11) -0.001(6) 0.042(8) -0.007(5) H123 0.077(10) 0.042(7) 0.093(13) 0.005(7) 0.063(10) 0.024(7) _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 C2 1.397(7) . ? C1 C9 1.438(6) . ? C1 C11 1.512(7) . ? C2 C3 1.408(8) . ? C2 H2 1.097(14) . ? C3 C4 1.376(8) . ? C3 H3 1.090(13) . ? C4 C10 1.424(7) . ? C4 H4 1.086(13) . ? C10 C5 1.421(7) . ? C10 C9 1.440(6) . ? C9 C8 1.444(6) . ? C8 C7 1.384(7) . ? C8 C12 1.515(7) . ? C7 C6 1.399(9) . ? C7 H7 1.087(12) . ? C6 C5 1.378(8) . ? C6 H6 1.082(14) . ? C5 H5 1.097(13) . ? C11 H111 1.097(12) . ? C11 H112 1.086(15) . ? C11 H113 1.077(15) . ? C12 H121 1.089(15) . ? C12 H122 1.070(14) . ? C12 H123 1.084(15) . ? 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 C2 C1 C9 119.0(4) . . ? C2 C1 C11 115.5(4) . . ? C9 C1 C11 125.5(4) . . ? C1 C2 C3 123.1(5) . . ? C1 C2 H2 117.2(9) . . ? C3 C2 H2 119.6(8) . . ? C4 C3 C2 118.8(4) . . ? C4 C3 H3 121.0(11) . . ? C2 C3 H3 120.2(11) . . ? C3 C4 C10 120.8(4) . . ? C3 C4 H4 120.3(9) . . ? C10 C4 H4 118.9(9) . . ? C5 C10 C4 118.1(4) . . ? C5 C10 C9 121.2(4) . . ? C4 C10 C9 120.7(4) . . ? C1 C9 C10 117.6(4) . . ? C1 C9 C8 125.3(4) . . ? C10 C9 C8 117.1(4) . . ? C7 C8 C9 119.2(4) . . ? C7 C8 C12 116.3(4) . . ? C9 C8 C12 124.5(5) . . ? C8 C7 C6 123.1(5) . . ? C8 C7 H7 118.0(9) . . ? C6 C7 H7 118.9(9) . . ? C5 C6 C7 119.6(5) . . ? C5 C6 H6 119.8(11) . . ? C7 C6 H6 120.6(11) . . ? C6 C5 C10 119.9(5) . . ? C6 C5 H5 121.6(10) . . ? C10 C5 H5 118.5(9) . . ? C1 C11 H111 112.0(8) . . ? C1 C11 H112 113.1(9) . . ? H111 C11 H112 108.4(12) . . ? C1 C11 H113 109.0(10) . . ? H111 C11 H113 109.0(16) . . ? H112 C11 H113 105.0(15) . . ? C8 C12 H121 111.9(9) . . ? C8 C12 H122 112.4(9) . . ? H121 C12 H122 109.5(14) . . ? C8 C12 H123 110.1(10) . . ? H121 C12 H123 107.4(13) . . ? H122 C12 H123 105.2(13) . . ? _refine_diff_density_max 0.128 _refine_diff_density_min -0.138 _refine_diff_density_rms 0.028