4-Phenylpyridinium betaine of squaric acid
Kolev, Tonsko; Wortmann, Rüdiger; Spiteller, Michael; Sheldrick, William Steven; Mayer-Figge, Heike; Acta Crystallographica Section E 61 (2005) o1090–o1092; doi:10.1107/S1600536805008457

data_2205425
_publ_section_title
;
 4-Phenylpyridinium betaine of squaric acid
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1090
_journal_page_last               o1092
_journal_paper_doi               10.1107/S1600536805008457
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C15 H9 N O3'
_chemical_formula_moiety         'C15 H9 N O3'
_chemical_formula_sum            'C15 H9 N O3'
_chemical_formula_weight         251.23
_chemical_name_common
;
4-Phenylpyridinium betaine of squaric acid
;
_chemical_name_systematic
;
4-phenylpyridinium-3-squarate
;
_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           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 91.49(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.852(3)
_cell_length_b                   12.924(3)
_cell_length_c                   7.236(2)
_cell_measurement_reflns_used    15
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      15
_cell_measurement_theta_min      7.5
_cell_volume                     1201.5(5)
_computing_cell_refinement       'R3m/V User's Guide'
_computing_data_collection       'R3m/V User's Guide (Siemens, 1989)'
_computing_data_reduction        'XDISK (Siemens, 1989)'
_computing_molecular_graphics    'SHELXTL-Plus (Sheldrick, 1995)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'Siemens P4 four-circle'
_diffrn_measurement_method       'Profile fitted'
_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  0.0378
_diffrn_reflns_av_sigmaI/netI    0.0451
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       1
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -1
_diffrn_reflns_number            2889
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.15
_diffrn_standards_decay_%        2
_diffrn_standards_interval_count 100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.098
_exptl_absorpt_correction_T_max  0.983
_exptl_absorpt_correction_T_min  0.957
_exptl_absorpt_correction_type   '\y scan'
_exptl_absorpt_process_details   '(XPREP in SHELXTL-Plus; Sheldrick, 1995)'
_exptl_crystal_colour            orange-red
_exptl_crystal_density_diffrn    1.389
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       prism
_exptl_crystal_F_000             520
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.21
_refine_diff_density_max         0.130
_refine_diff_density_min         -0.159
_refine_ls_extinction_coef       0.037(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.037
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     173
_refine_ls_number_reflns         2112
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.037
_refine_ls_R_factor_all          0.0686
_refine_ls_R_factor_gt           0.0427
_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^)+(0.0532P)^2^+0.0499P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1013
_refine_ls_wR_factor_ref         0.1117
_reflns_number_gt                1455
_reflns_number_total             2112
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bt6631.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_cell_volume        1201.4(5)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2205425
_cod_database_fobs_code          2205425