Two fluoradene derivatives: pseudosymmetry, eccentric ellipsoids and a phase transition
Xia, Aibing; Selegue, John P.; Carrillo, Alberto; Patrick, Brian O.; Parkin, Sean; Brock, Carolyn Pratt; Acta Crystallographica Section B 57 (2001) 507–516; doi:10.1107/S0108768101008631

data_2103699
_publ_section_title
;
 Two fluoradene derivatives: pseudosymmetry, eccentric ellipsoids and a
 phase transition
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              507
_journal_page_last               516
_journal_paper_doi               10.1107/S0108768101008631
_journal_volume                  57
_journal_year                    2001
_chemical_formula_moiety         'C25 H14 N2 O4'
_chemical_formula_sum            'C25 H14 N2 O4'
_chemical_formula_weight         406.38
_chemical_melting_point          513.15
_chemical_name_systematic
;
7b-(2,4-dinitrophenyl)fluoradene
;
_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'
_audit_creation_method
;
SHELXL-97, macros written locally, and C. P. Brock
;
_cell_angle_alpha                90
_cell_angle_beta                 110.040(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.722(2)
_cell_length_b                   15.513(4)
_cell_length_c                   17.111(4)
_cell_measurement_reflns_used    18571
_cell_measurement_temperature    295.0(10)
_cell_measurement_theta_max      25.0
_cell_measurement_theta_min      1.0
_cell_volume                     1925.6(8)
_computing_cell_refinement       'DENZO-SMN (Otwinowski & Minor, 1997)'
_computing_data_collection       'COLLECT software (Nonius, 1998)'
_computing_data_reduction        'SCALEPACK (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'SHELXTL PC (Sheldrick, 1990)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution
;
Starting model from full structure (a=15.444;  two independent
molecules in the asymmetric unit)
;
_diffrn_ambient_temperature      295.0(10)
_diffrn_detector_area_resol_mean 18
_diffrn_measured_fraction_theta_full .996
_diffrn_measured_fraction_theta_max .996
_diffrn_measurement_device_type  'Nonius KappaCCD diffractometer'
_diffrn_measurement_method       '\f and \w scans with 2.0\% steps'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .021
_diffrn_reflns_av_sigmaI/netI    .048
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            6094
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.0
_diffrn_reflns_theta_min         2.6
_diffrn_standards_decay_%        <1.
_exptl_absorpt_coefficient_mu    .097
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            'dark orange'
_exptl_crystal_density_diffrn    1.402
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'Prism.  Major faces are {011} and {010}'
_exptl_crystal_F_000             840
_exptl_crystal_size_max          .50
_exptl_crystal_size_mid          .20
_exptl_crystal_size_min          .20
_refine_diff_density_max         .38
_refine_diff_density_min         -.40
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.03
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     280
_refine_ls_number_reflns         3377
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.03
_refine_ls_R_factor_all          .113
_refine_ls_R_factor_gt           .086
_refine_ls_shift/su_max          .001
_refine_ls_shift/su_mean         .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.042P)^2^+3.3P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .185
_reflns_number_gt                2505
_reflns_number_total             3377
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            bs0015.cif
_cod_data_source_block           PseuFlda
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '240_C' was changed to '513.15' - it
was converted from degrees Celsius(C) to Kelvins(K).

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 '240_C' was changed to '513.15' - it
was converted from degrees Celsius(C) to Kelvins(K).

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      'P1 21/c 1'
_cod_database_code               2103699
_cod_database_fobs_code          2103699