2,5-Diphenyl-3,6-dihydroxy-1,4-benzoquinone (polyporic acid)
Cohen, Peter A.; Robinson, Paul D.; Acta Crystallographica Section E 57 (2001) o596–o598; doi:10.1107/S160053680100914X

data_2200415
_publ_section_title
;
 2,5-Diphenyl-3,6-dihydroxy-1,4-benzoquinone (polyporic acid)
;
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o596
_journal_page_last               o598
_journal_paper_doi               10.1107/S160053680100914X
_journal_volume                  57
_journal_year                    2001
_chemical_formula_iupac          'C18 H12 O4'
_chemical_formula_moiety         'C18 H12 O4'
_chemical_formula_sum            'C18 H12 O4'
_chemical_formula_weight         292.28
_chemical_melting_point          580.0(10)
_chemical_name_systematic
;
2,5-Diphenyl-3,6-dihydroxy-1,4-benzoquinone
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.323(3)
_cell_length_b                   26.980(4)
_cell_length_c                   6.897(4)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    296
_cell_measurement_theta_max      24.3
_cell_measurement_theta_min      20.8
_cell_volume                     1362.7(10)
_computing_cell_refinement
;
MSC/AFC Diffractometer Control Software
(Molecular Structure Corporation, 1996)
;
_computing_data_collection
;
MSC/AFC Diffractometer Control Software
(Molecular Structure Corporation, 1996)
;
_computing_data_reduction
;
PROCESS in TEXSAN  (Molecular Structure Corporation, 1997)
;
_computing_molecular_graphics    'ORTEP (Johnson, 1965) in TEXSAN'
_computing_publication_material
;
TEXSAN, SHELXL97 and PLATON (Spek, 2000)
;
_computing_structure_refinement  'LS in TEXSAN and SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR92 (Burla et al., 1989)'
_diffrn_ambient_temperature      296
_diffrn_measured_fraction_theta_full .999
_diffrn_measured_fraction_theta_max .999
_diffrn_measurement_device_type  'Rigaku AFC-5S'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     .71069
_diffrn_reflns_av_R_equivalents  0
_diffrn_reflns_av_sigmaI/netI    .027
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       32
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1201
_diffrn_reflns_theta_full        25.02
_diffrn_reflns_theta_max         25.02
_diffrn_reflns_theta_min         3.02
_diffrn_standards_decay_%        .3
_diffrn_standards_interval_count 199
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    .101
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            'dark red'
_exptl_crystal_density_diffrn    1.425
_exptl_crystal_density_meas      ?
_exptl_crystal_description       prism
_exptl_crystal_F_000             608
_exptl_crystal_size_max          .49
_exptl_crystal_size_mid          .39
_exptl_crystal_size_min          .33
_refine_diff_density_max         .14
_refine_diff_density_min         -.24
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.019
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     101
_refine_ls_number_reflns         1201
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.019
_refine_ls_R_factor_all          .068
_refine_ls_R_factor_gt           .035
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0592P)^2^+0.1614P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .110
_reflns_number_gt                796
_reflns_number_total             1201
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            cf6080.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '579-581' was changed to '580.0(10)'
- the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_chemical_melting_point' value '579-581' was changed to '580.0(10)'
- the average value was taken and precision was estimated.

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_cell_volume        1362.7(9)
_cod_database_code               2200415
_cod_database_fobs_code          2200415