The inner salt 4-carboxy-2-(pyridinium-4-yl)-1<i>H</i>-imidazole-5-carboxylate monohydrate
Sun, Ting; Ma, Jian-Ping; Huang, Ru-Qi; Dong, Yu-Bin; Acta Crystallographica Section E 62 (2006) o2751–o2752; doi:10.1107/S1600536806020356

data_2209704
_publ_section_title
;
 The inner salt
 4-carboxy-2-(pyridinium-4-yl)-1<i>H</i>-imidazole-5-carboxylate
 monohydrate
;
_journal_coeditor_code           XU2042
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o2751
_journal_page_last               o2752
_journal_paper_doi               10.1107/S1600536806020356
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C10 H7 N3 O4, H2 O'
_chemical_formula_moiety         'C10 H7 N3 O4, H2 O'
_chemical_formula_sum            'C10 H9 N3 O5'
_chemical_formula_weight         251.20
_chemical_name_systematic
;
4-carboxy-2-(pyridinium-4-yl)-1H-imidazole-5-dicarboxylate monohydrate
;
_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                 94.889(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.6348(15)
_cell_length_b                   8.457(2)
_cell_length_c                   21.605(6)
_cell_measurement_reflns_used    1068
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      23.4
_cell_measurement_theta_min      2.6
_cell_volume                     1025.8(5)
_computing_cell_refinement       'SAINT (Bruker, 2000)'
_computing_data_collection       'SMART (Bruker, 2000)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL (Bruker, 2000)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 1.00
_diffrn_measured_fraction_theta_max 1.00
_diffrn_measurement_device_type  'Bruker SMART CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_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  0.034
_diffrn_reflns_av_sigmaI/netI    0.043
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            5216
_diffrn_reflns_theta_full        25.5
_diffrn_reflns_theta_max         25.5
_diffrn_reflns_theta_min         1.9
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.133
_exptl_absorpt_correction_T_max  0.990
_exptl_absorpt_correction_T_min  0.966
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2000)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.627
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       planete
_exptl_crystal_F_000             520
_exptl_crystal_size_max          0.26
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.24
_refine_diff_density_min         -0.23
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.120
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     163
_refine_ls_number_reflns         1912
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.120
_refine_ls_R_factor_all          0.066
_refine_ls_R_factor_gt           0.051
_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^)+(0.0437P)^2^+0.2198P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.105
_refine_ls_wR_factor_ref         0.111
_reflns_number_gt                1541
_reflns_number_total             1912
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            xu2042.cif
_cod_data_source_block           I
_cod_original_cell_volume        1025.7(5)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2209704
_cod_database_fobs_code          2209704