Quinoxalinium 2,6-dihydroxybenzoate
Czapik, Agnieszka; Gdaniec, Maria; Acta Crystallographica Section E 63 (2007) o1480–o1482; doi:10.1107/S1600536807008707

data_2212452
_publ_section_title
;
 Quinoxalinium 2,6-dihydroxybenzoate
;
_journal_coeditor_code           BH2084
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1480
_journal_page_last               o1482
_journal_paper_doi               10.1107/S1600536807008707
_journal_volume                  63
_journal_year                    2007
_chemical_formula_iupac          'C8 H7 N2 +, C7 H5 O4 -'
_chemical_formula_moiety         'C8 H7 N2 +, C7 H5 O4 -'
_chemical_formula_sum            'C15 H12 N2 O4'
_chemical_formula_weight         284.27
_chemical_melting_point          393
_chemical_name_systematic
;
quinoxalinium 2,6-dihydroxybenzoate
;
_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
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 102.872(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   12.0557(5)
_cell_length_b                   9.0755(4)
_cell_length_c                   24.7931(10)
_cell_measurement_reflns_used    7496
_cell_measurement_temperature    294(2)
_cell_measurement_theta_max      29.48
_cell_measurement_theta_min      2.52
_cell_volume                     2644.48(19)
_computing_cell_refinement       'CrysAlis CCD'
_computing_data_collection       'CrysAlis CCD (Oxford Diffraction, 2006)'
_computing_data_reduction        'CrysAlis RED (Oxford Diffraction, 2006)'
_computing_molecular_graphics
;
Stereochemical Workstation Operation Manual (Siemens, 1989)
and MERCURY (Macrae <i>et al.</i>,  2006)
;
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      294(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Kuma KM-4-CCD \k geometry'
_diffrn_measurement_method       \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  0.0203
_diffrn_reflns_av_sigmaI/netI    0.0112
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            14871
_diffrn_reflns_theta_full        26.37
_diffrn_reflns_theta_max         26.37
_diffrn_reflns_theta_min         4.10
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.106
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            light-brown
_exptl_crystal_density_diffrn    1.428
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1184
_exptl_crystal_size_max          0.6
_exptl_crystal_size_mid          0.6
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.151
_refine_diff_density_min         -0.150
_refine_ls_extinction_coef       0.0019(5)
_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   1.089
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     203
_refine_ls_number_reflns         2701
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.089
_refine_ls_R_factor_all          0.0618
_refine_ls_R_factor_gt           0.0408
_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^)+(0.0514P)^2^+1.2986P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1057
_refine_ls_wR_factor_ref         0.1268
_reflns_number_gt                1935
_reflns_number_total             2701
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bh2084.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2212452
_cod_database_fobs_code          2212452