data_2100451 loop_ _publ_author_name 'Barnett, Sarah A.' 'Broder, Charlotte K.' 'Shankland, Kenneth' 'David, Bill I. F.' 'Ibberson, Richard' 'Tocher, Derek A.' _publ_section_title ; Single crystal X-ray and neutron powder diffraction investigation of the phase transition in tetrachlorobenzene ; _journal_coeditor_code SO5001 _journal_date_accepted 2005-12-15 _journal_date_recd_electronic 2005-10-19 _journal_issue 2 _journal_name_full 'Acta Crystallographica, Section B' _journal_page_first 287 _journal_page_last 295 _journal_paper_category FA _journal_volume 62 _journal_year 2006 _chemical_formula_moiety 'C6 Cl4 D2' _chemical_formula_structural 'C6 D2 Cl4' _chemical_formula_sum 'C6 Cl4 D2' _chemical_formula_weight 217.88 _chemical_melting_point ? _chemical_name_common '1,2,4,5-tetrachlorobenzene - beta polymorph' _chemical_name_systematic ; 1,2,4,5-tetrachlorobenzene ; _symmetry_cell_setting Monoclinic _symmetry_space_group_name_Hall ? _symmetry_space_group_name_H-M P21/n _cell_angle_alpha 90 _cell_angle_beta 99.7088(5) _cell_angle_gamma 90 _cell_formula_units_Z 2 _cell_length_a 3.81117(4) _cell_length_b 10.53867(4) _cell_length_c 9.57198(3) _cell_measurement_reflns_used 1118 _cell_measurement_temperature 200(2) _cell_measurement_theta_max ? _cell_measurement_theta_min ? _cell_volume 378.949(4) _computing_data_collection 'custom ISIS software' _computing_data_reduction 'custom ISIS software' _computing_structure_refinement 'Topas v3.1 (Coehlo, 2003)' _computing_structure_solution ? _diffrn_ambient_temperature 200(2) _diffrn_measurement_device_type 'HRPD, ISIS' _diffrn_radiation_monochromator ? _diffrn_radiation_type Neutron _diffrn_radiation_wavelength ? _diffrn_reflns_limit_h_max 5 _diffrn_reflns_limit_h_min 0 _diffrn_reflns_limit_k_max 14 _diffrn_reflns_limit_k_min -14 _diffrn_reflns_limit_l_max 13 _diffrn_reflns_limit_l_min -13 _diffrn_reflns_number 1118 _exptl_absorpt_coefficient_mu 0.51 _exptl_absorpt_correction_T_max ? _exptl_absorpt_correction_T_min ? _exptl_absorpt_correction_type empirical _exptl_absorpt_process_details ; Mu = 0.51cm^-1^ at 1.8\A calculated using custom ISIS software program Arial Mucalc ; _exptl_crystal_density_diffrn ? _exptl_crystal_density_meas ? _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 ? _refine_diff_density_max ? _refine_diff_density_min ? _refine_ls_extinction_coef ? _refine_ls_extinction_method none _refine_ls_goodness_of_fit_all 1.261 _refine_ls_hydrogen_treatment refxyz _refine_ls_matrix_type sparse _refine_ls_number_constraints 2 _refine_ls_number_parameters 38 _refine_ls_number_restraints 11 _refine_ls_shift/su_max 0.001 _refine_ls_weighting_details ? _refine_ls_weighting_scheme sigma loop_ _symmetry_equiv_pos_site_id _symmetry_equiv_pos_as_xyz 1 x,y,z 2 1/2-x,1/2+y,1/2-z 3 -x,-y,-z 4 1/2+x,1/2-y,1/2+z loop_ _atom_site_type_symbol _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_calc_flag _atom_site_occupancy _atom_site_disorder_assembly _atom_site_disorder_group C C1 0.0651(4) 0.46742(9) 0.36540(7) 2.36(4) Biso d 1 . . C C2 -0.0139(5) 0.37337(11) 0.45843(9) 2.36(4) Biso d 1 . . C C3 0.0861(5) 0.59328(13) 0.40957(9) 2.36(4) Biso d 1 . . Cl Cl1 0.1523(4) 0.42918(9) 0.20027(10) 3.11(4) Biso d 1 . . Cl Cl2 -0.0422(4) 0.21672(10) 0.40643(9) 3.11(4) Biso d 1 . . D H1 0.1512(6) 0.66550(13) 0.33866(14) 3.48(5) Biso d 1 . . 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' Cl Cl 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_2 _geom_angle_site_symmetry_3 _geom_angle _geom_angle_publ_flag Cl1 C1 C2 . . . 121.04(8) ? Cl1 C1 C3 . . . 119.58(8) ? C2 C1 C3 . . . 119.34(8) ? Cl2 C2 C1 . . . 120.33(8) ? Cl2 C2 C3 . . 3_566 119.68(10) ? C1 C2 C3 . . 3_566 119.93(11) ? C1 C3 C2 . . 3_566 120.67(11) ? C1 C3 H1 . . . 119.37(12) ? H1 C3 C2 . . 3_566 119.93(14) ? loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_site_symmetry_1 _geom_bond_site_symmetry_2 _geom_bond_distance _geom_bond_publ_flag Cl1 C1 . . 1.7171(13) ? Cl2 C2 . . 1.7224(15) ? C1 C2 . . 1.3987(15) ? C1 C3 . . 1.3904(16) ? C2 C3 . 3_566 1.3831(15) ? C3 H1 . . 1.076(2) ? 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_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion _geom_torsion_publ_flag Cl1 C1 C2 Cl2 . . . . -2.5(2) ? Cl1 C1 C2 C3 . . . 3_566 -179.46(14) ? C3 C1 C2 Cl2 . . . . 179.91(13) ? C3 C1 C2 C3 . . . 3_566 2.9(2) ? Cl1 C1 C3 C2 . . . 3_566 179.40(15) ? C2 C1 C3 C2 . . . 3_566 -3.0(2) ? Cl2 C2 C3 C1 . . 3_566 3_566 -179.97(14) ? C1 C2 C3 C1 . . 3_566 3_566 -3.0(3) ? Cl1 C1 C3 H1 . . . . 1.4(3) ? C2 C1 C3 H1 . . . . 179.0(2) ? Cl2 C2 C3 H1 . . 3_566 3_566 2.0(3) ? C1 C2 C3 H1 . . 3_566 3_566 179.0(2) ?