An orthorhombic polymorph of 2,3,2',3'-tetrakis(2-pyridyl)-6,6'-biquinoxalinyl
Antonia Neels; Helen Stoeckli-Evans; Acta Crystallographica Section E 59 (2003) o2030–o2031; doi:10.1107/S1600536803027004

data_2202765
_publ_section_title
;
 An orthorhombic polymorph of
 2,3,2',3'-tetrakis(2-pyridyl)-6,6'-biquinoxalinyl
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o2030
_journal_page_last               o2031
_journal_paper_doi               10.1107/S1600536803027004
_journal_volume                  59
_journal_year                    2003
_chemical_formula_iupac          'C36 H22 N8'
_chemical_formula_moiety         'C36 H22 N8'
_chemical_formula_sum            'C36 H22 N8'
_chemical_formula_weight         566.62
_chemical_name_systematic
;
2,3,2',3'-tetrakis(2-pyridyl)-6,6'-biquinoxalinyl
;
_space_group_IT_number           43
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'F 2 -2d'
_symmetry_space_group_name_H-M   'F d d 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   21.0806(19)
_cell_length_b                   20.338(2)
_cell_length_c                   12.8637(13)
_cell_measurement_reflns_used    3165
_cell_measurement_temperature    223(2)
_cell_measurement_theta_max      25.90
_cell_measurement_theta_min      2.28
_cell_volume                     5515.1(9)
_computing_cell_refinement       'CELL (Stoe, 2000)'
_computing_data_collection       'EXPOSE (Stoe, 2000)'
_computing_data_reduction        'INTEGRATE (Stoe, 2000)'
_computing_molecular_graphics    'PLATON99 (Spek, 1990)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      223(2)
_diffrn_detector_area_resol_mean 0.81\%A
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'STOE IPDS'
_diffrn_measurement_method       \f
_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  0.1069
_diffrn_reflns_av_sigmaI/netI    0.0959
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            10285
_diffrn_reflns_theta_full        25.87
_diffrn_reflns_theta_max         25.87
_diffrn_reflns_theta_min         2.11
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.085
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.365
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             2352
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.185
_refine_diff_density_min         -0.221
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.700
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     199
_refine_ls_number_reflns         1396
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.700
_refine_ls_R_factor_all          0.0861
_refine_ls_R_factor_gt           0.0363
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         <0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0536P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0735
_refine_ls_wR_factor_ref         0.0866
_reflns_number_gt                775
_reflns_number_total             1396
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            na6274.cif
_cod_data_source_block           II
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'none' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_database_code               2202765
_cod_database_fobs_code          2202765