Proton sharing in bis(4-carbamoylpyridinium) squarate
Köroglu, Ahmet; Bulut, Ahmet; Uçar, Ibrahim; Nichol, Gary S.; Harrington, Ross W.; Clegg, William; Acta Crystallographica Section C 61 (2005) o678–o680; doi:10.1107/S0108270105032622

data_2015204
_publ_section_title
;
 Proton sharing in bis(4-carbamoylpyridinium) squarate
;
_journal_coeditor_code           SK1874
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o678
_journal_page_last               o680
_journal_paper_doi               10.1107/S0108270105032622
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          '2C6 H6 N2 O +, C4 H2 O4 2-'
_chemical_formula_moiety         '2C6 H6 N2 O +, C4 H2 O4 2-'
_chemical_formula_sum            'C16 H14 N4 O6'
_chemical_formula_weight         358.32
_chemical_name_common            'Diisonicotinamidium squarate'
_chemical_name_systematic
;
bis(4-carbamoylpyridinium) squarate
;
_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   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 104.93(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.959(2)
_cell_length_b                   10.691(2)
_cell_length_c                   12.257(3)
_cell_measurement_reflns_used    4241
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      2.5
_cell_volume                     1514.2(6)
_computing_cell_refinement       'EvalCCD (Duisenberg et al., 2003)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction        EvalCCD
_computing_molecular_graphics    'DIAMOND (Brandenburg & Putz, 2004)'
_computing_publication_material
;
SHELXTL, WinGX (Farrugia, 1999) and local programs
;
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 2001)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0511
_diffrn_reflns_av_sigmaI/netI    0.0394
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            10470
_diffrn_reflns_theta_full        27.50
_diffrn_reflns_theta_max         27.50
_diffrn_reflns_theta_min         3.93
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.123
_exptl_absorpt_correction_T_max  0.985
_exptl_absorpt_correction_T_min  0.911
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2003)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.572
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             744
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.29
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.348
_refine_diff_density_min         -0.237
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.034
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     130
_refine_ls_number_reflns         1731
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.034
_refine_ls_R_factor_all          0.0608
_refine_ls_R_factor_gt           0.0387
_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^)+(0.0522P)^2^+0.9909P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0954
_refine_ls_wR_factor_ref         0.1051
_reflns_number_gt                1318
_reflns_number_total             1731
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            sk1874.cif
_cod_data_source_block           I
_cod_original_cell_volume        1514.3(6)
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2015204
_cod_database_fobs_code          2015204