Pyridinium 5-carboxypyrazine-2-carboxylate
Xian-Zhi Guo; Sheng-Min Hao; Bao-Long Zhang; Acta Crystallographica Section E 62 (2006) o4462–o4463; doi:10.1107/S160053680603039X

data_2210825
_publ_section_title
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 Pyridinium 5-carboxypyrazine-2-carboxylate
;
_journal_coeditor_code           XU2105
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o4462
_journal_page_last               o4463
_journal_paper_doi               10.1107/S160053680603039X
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C5 H6 N +, C6 H3 N2 O4 -'
_chemical_formula_moiety         'C5 H6 N +, C6 H3 N2 O4 -'
_chemical_formula_sum            'C11 H9 N3 O4'
_chemical_formula_weight         247.21
_chemical_name_systematic
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Pyridinium 5-carboxypyrazine-2-carboxylate
;
_space_group_IT_number           11
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yb'
_symmetry_space_group_name_H-M   'P 1 21/m 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                 115.905(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   9.237(2)
_cell_length_b                   6.7553(18)
_cell_length_c                   9.529(3)
_cell_measurement_reflns_used    1432
_cell_measurement_temperature    294(2)
_cell_measurement_theta_max      26.4
_cell_measurement_theta_min      2.3
_cell_volume                     534.9(2)
_computing_cell_refinement       'SAINT (Bruker, 2003)'
_computing_data_collection       'SMART (Bruker, 2003)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL (Sheldrick, 1997b)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997a)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997a)'
_diffrn_ambient_temperature      294(2)
_diffrn_measured_fraction_theta_full 0.99
_diffrn_measured_fraction_theta_max 0.99
_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  0.019
_diffrn_reflns_av_sigmaI/netI    0.021
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            3034
_diffrn_reflns_theta_full        26.4
_diffrn_reflns_theta_max         26.4
_diffrn_reflns_theta_min         2.4
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.120
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.535
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             256
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.22
_refine_diff_density_min         -0.17
_refine_ls_extinction_coef       0.046(8)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.083
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     109
_refine_ls_number_reflns         1195
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.083
_refine_ls_R_factor_all          0.046
_refine_ls_R_factor_gt           0.036
_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^)+(0.0544P)^2^+0.1076P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.100
_refine_ls_wR_factor_ref         0.109
_reflns_number_gt                943
_reflns_number_total             1195
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            xu2105.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'P 21/m'
_cod_database_code               2210825
_cod_database_fobs_code          2210825