Concomitant but disappearing: two polymorphs of 1,4-bis(tribromomethyl)benzene
Jones, Peter G.; Hopf, Henning; Silaghi, Anamaria; Näther, Christian; Acta Crystallographica Section C 67 (2011) o405–o408; doi:10.1107/S0108270111037930

data_2018248
_publ_section_title
;
 Concomitant but disappearing: two polymorphs of
 1,4-bis(tribromomethyl)benzene
;
_journal_coeditor_code           FA3260
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o405
_journal_page_last               o408
_journal_paper_doi               10.1107/S0108270111037930
_journal_volume                  67
_journal_year                    2011
_chemical_formula_iupac          'C8 H4 Br6'
_chemical_formula_moiety         'C8 H4 Br6'
_chemical_formula_sum            'C8 H4 Br6'
_chemical_formula_weight         579.57
_chemical_name_systematic
;
1,4-bis(tribromomethyl)benzene
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 102.152(9)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.1640(9)
_cell_length_b                   6.5048(7)
_cell_length_c                   19.3410(17)
_cell_measurement_reflns_used    5599
_cell_measurement_temperature    103(2)
_cell_measurement_theta_max      75.7158
_cell_measurement_theta_min      4.6729
_cell_volume                     1250.1(2)
_computing_cell_refinement       'CrysAlis PRO (Oxford Diffraction, 2009)'
_computing_data_collection       'CrysAlis PRO (Oxford Diffraction, 2009)'
_computing_data_reduction        'CrysAlis PRO (Oxford Diffraction, 2009)'
_computing_molecular_graphics    'XP (Siemens, 1994)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      103(2)
_diffrn_detector_area_resol_mean 10.3543
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.967
_diffrn_measurement_device_type  'Oxford Xcalibur Nova Atlas'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_source         'Nova (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0755
_diffrn_reflns_av_sigmaI/netI    0.0317
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            7801
_diffrn_reflns_theta_full        72.50
_diffrn_reflns_theta_max         75.90
_diffrn_reflns_theta_min         4.68
_exptl_absorpt_coefficient_mu    22.886
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.43918
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'CrysAlis PRO (Oxford Diffraction, 2009)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.080
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'hexagonal plate'
_exptl_crystal_F_000             1048
_exptl_crystal_size_max          0.04
_exptl_crystal_size_mid          0.04
_exptl_crystal_size_min          0.015
_refine_diff_density_max         1.023
_refine_diff_density_min         -0.926
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     64
_refine_ls_number_reflns         1271
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.052
_refine_ls_R_factor_all          0.0406
_refine_ls_R_factor_gt           0.0368
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0769P)^2^+1.4614P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0998
_refine_ls_wR_factor_ref         0.1028
_reflns_number_gt                1163
_reflns_number_total             1271
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fa3260.cif
_cod_data_source_block           Ib
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2018248
_cod_database_fobs_code          2018248