4-Nitrobenzoic acid–2,2'-biimidazole (2/1)
Liu, Xin; Zhu, Weiqun; Acta Crystallographica Section E 66 (2010) o1245–; doi:10.1107/S1600536810015643

data_2226071
_publ_section_title
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 4-Nitrobenzoic acid--2,2'-biimidazole (2/1)
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_journal_coeditor_code           BX2278
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1245
_journal_paper_doi               10.1107/S1600536810015643
_journal_volume                  66
_journal_year                    2010
_chemical_formula_iupac          '2C7 H5 N O4, C6 H6 N4'
_chemical_formula_moiety         '2(C7 H5 N O4), C6 H6 N4'
_chemical_formula_sum            'C20 H16 N6 O8'
_chemical_formula_weight         468.38
_chemical_name_systematic
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4-Nitrobenzoic acid--2,2'-biimidazole (2/1)
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 90.4960(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   4.8520(10)
_cell_length_b                   10.9245(10)
_cell_length_c                   19.7981(10)
_cell_measurement_reflns_used    1230
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      22.00
_cell_measurement_theta_min      2.78
_cell_volume                     1049.4(2)
_computing_cell_refinement       'SAINT-Plus (Bruker, 2001)'
_computing_data_collection       'APEX2 (Bruker, 2004)'
_computing_data_reduction        'SAINT-Plus (Bruker, 2001)'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 2008)'
_computing_publication_material  'SHELXTL (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEXII CCD'
_diffrn_measurement_method       'phi and omega 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  0.0336
_diffrn_reflns_av_sigmaI/netI    0.0407
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            5185
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.06
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.118
_exptl_absorpt_correction_T_max  0.9906
_exptl_absorpt_correction_T_min  0.9860
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2001)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.482
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             484
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.247
_refine_diff_density_min         -0.148
_refine_ls_extinction_coef       0.013(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 2008)'
_refine_ls_goodness_of_fit_ref   0.999
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     158
_refine_ls_number_reflns         1849
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.001
_refine_ls_R_factor_all          0.0687
_refine_ls_R_factor_gt           0.0447
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0780P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1187
_refine_ls_wR_factor_ref         0.1340
_reflns_number_gt                1264
_reflns_number_total             1849
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bx2278.cif
_cod_data_source_block           I
_cod_depositor_comments
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2019-10-26
Z value and formula fixed to values more according to usual
chemical conventions.                 miguel
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_cod_original_sg_symbol_H-M      'P 21/c'
_cod_original_formula_moiety     'C7 H5 N O4, 0.5(C6 H6 N4)'
_cod_original_formula_iupac      'C7 H5 N O4, 0.5C6 H6 N4'
_cod_original_formula_sum        'C10 H8 N3 O4'
_cod_original_formula_units_Z    4
_cod_original_formula_weight     234.19
_cod_database_code               2226071
_cod_database_fobs_code          2226071