2-(3-Benzoyl-1-pyridinio)-3,4-dioxocyclobutenolate
Tsonko Kolev; Denitsa Yancheva; Boris Shivachev; Rosica Petrova; Michael Spiteller; Acta Crystallographica Section C 61 (2005) o213–o215; doi:10.1107/S0108270105003069

data_2014863
_publ_section_title
;
 2-(3-Benzoyl-1-pyridinio)-3,4-dioxocyclobutenolate
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o213
_journal_page_last               o215
_journal_paper_doi               10.1107/S0108270105003069
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C16 H9 N O4'
_chemical_formula_moiety         'C16 H9 N O4'
_chemical_formula_sum            'C16 H9 N O4'
_chemical_formula_weight         279.24
_chemical_melting_point          418
_chemical_name_common            '3-benzoylpyridinium betaine of squaric acid'
_chemical_name_systematic
;
2-(3-Benzoyl-1-pyridinio)-3,4-dioxocyclobutenolate
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 103.903(12)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.9319(11)
_cell_length_b                   13.6577(14)
_cell_length_c                   12.0890(12)
_cell_measurement_reflns_used    22
_cell_measurement_temperature    290(2)
_cell_measurement_theta_max      19.60
_cell_measurement_theta_min      18.39
_cell_volume                     1271.3(3)
_computing_cell_refinement       'CAD-4 EXPRESS'
_computing_data_collection       'CAD-4 EXPRESS (Enraf-Nonius, 1994)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_molecular_graphics    'ORTEP-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      290
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device       '\k-geometry diffractometer'
_diffrn_measurement_device_type  'Enraf-Nonius CAD-4'
_diffrn_measurement_method       'non-profiled \w/2\q'
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0929
_diffrn_reflns_av_sigmaI/netI    0.0889
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            6407
_diffrn_reflns_theta_full        27.98
_diffrn_reflns_theta_max         27.98
_diffrn_reflns_theta_min         2.29
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.459
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       cubic
_exptl_crystal_F_000             576
_exptl_crystal_size_max          0.24
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.24
_refine_diff_density_max         0.293
_refine_diff_density_min         -0.342
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.036
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     190
_refine_ls_number_reflns         3063
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.036
_refine_ls_R_factor_all          0.1423
_refine_ls_R_factor_gt           0.0673
_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^)+(0.1235P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1832
_refine_ls_wR_factor_ref         0.2363
_reflns_number_gt                1558
_reflns_number_total             3063
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ob1218.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 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2014863
_cod_database_fobs_code          2014863