Planar packing of tetrachlorodicyanobenzene isomers
Britton, Doyle; Acta Crystallographica, Section B: Structural Science 58 (2002) 553–563; doi:10.1107/S0108768102003348

data_2103108
_publ_section_title
;
 Planar packing of tetrachlorodicyanobenzene isomers
;
_journal_coden_ASTM              ASBSDK
_journal_issue                   3
_journal_name_full
;
 Acta Crystallographica, Section B: Structural Science
;
_journal_page_first              553
_journal_page_last               563
_journal_paper_doi               10.1107/S0108768102003348
_journal_volume                  58
_journal_year                    2002
_chemical_formula_moiety         'C12 H18, C8 Cl4 N2'
_chemical_formula_sum            'C20 H18 Cl4 N2'
_chemical_formula_weight         428.16
_chemical_name_systematic
;
 para tetrachlorodicyanobenzene/hexamethylbenzene, 1/1
 polymorph I
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'SHELXTL plus manual additions'
_cell_angle_alpha                114.24(3)
_cell_angle_beta                 113.30(2)
_cell_angle_gamma                91.92(3)
_cell_formula_units_Z            1
_cell_length_a                   7.513(3)
_cell_length_b                   8.615(3)
_cell_length_c                   9.029(3)
_cell_measurement_reflns_used    24
_cell_measurement_temperature    189(2)
_cell_measurement_theta_max      28
_cell_measurement_theta_min      11
_cell_volume                     475.8(3)
_computing_cell_refinement       'CAD-4 software'
_computing_data_collection       'CAD-4 software'
_computing_data_reduction        TEXSAN
_computing_molecular_graphics    'TEXSAN, SHELXTL'
_computing_structure_refinement  'SHELXTL (Sheldrick, 1994)'
_computing_structure_solution    'TEXSAN, MITHRIL, DIRDIF'
_diffrn_ambient_temperature      189(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  CAD-4
_diffrn_measurement_method       'omega-two theta scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.074
_diffrn_reflns_av_sigmaI/netI    0.083
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            4293
_diffrn_reflns_theta_full        29.98
_diffrn_reflns_theta_max         29.98
_diffrn_reflns_theta_min         2.67
_diffrn_standards_decay_%        'less than 1'
_diffrn_standards_interval_time  '60 min'
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.629
_exptl_absorpt_correction_T_max  0.91
_exptl_absorpt_correction_T_min  0.75
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
  DIFABS, Walker, N. and Stuart, D. (1983) Acta Cryst. A39, 158-166.
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.494
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       sword-shaped
_exptl_crystal_F_000             220
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.571
_refine_diff_density_min         -0.647
_refine_ls_extinction_coef       0.09(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXTL
_refine_ls_goodness_of_fit_ref   1.095
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     122
_refine_ls_number_reflns         2775
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.095
_refine_ls_R_factor_all          0.0848
_refine_ls_R_factor_gt           0.0737
_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^)+(0.098P)^2^+0.96P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2028
_refine_ls_wR_factor_ref         0.2115
_reflns_number_gt                2324
_reflns_number_total             2775
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            bk0105.cif
_cod_database_code               2103108