Photoinduced ground-state singlet biradical???novel insight into the photochromic compounds of biindenylidenediones
Xu, Lili; Sugiyama, Teruki; Huang, Huaming; Song, Zhiji; Meng, Jiben; Matsuura, Teruo; Chemical Communications  (2002) 2328–; doi:10.1039/b206876a

data_7114248
_publ_section_title
;
 Photoinduced ground-state singlet biradical???novel insight into the
 photochromic compounds of biindenylidenediones
;
_journal_issue                   20
_journal_name_full               'Chemical Communications'
_journal_page_first              2328
_journal_paper_doi               10.1039/b206876a
_journal_year                    2002
_chemical_formula_sum            'C24 H24 O4'
_chemical_formula_weight         376.43
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 105.014(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.398(3)
_cell_length_b                   12.481(4)
_cell_length_c                   15.371(4)
_cell_measurement_temperature    293(2)
_cell_volume                     1926.7(10)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0633
_diffrn_reflns_av_sigmaI/netI    0.0749
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            4885
_diffrn_reflns_theta_full        25.02
_diffrn_reflns_theta_max         25.02
_diffrn_reflns_theta_min         2.60
_diffrn_standards_decay_%        2
_exptl_absorpt_coefficient_mu    0.087
_exptl_absorpt_correction_T_max  0.9827
_exptl_absorpt_correction_T_min  0.9743
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            Yellow
_exptl_crystal_density_diffrn    1.298
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Rhombic
_exptl_crystal_F_000             800
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.206
_refine_diff_density_min         -0.165
_refine_diff_density_rms         0.041
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.989
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     127
_refine_ls_number_reflns         1712
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.989
_refine_ls_R_factor_all          0.1117
_refine_ls_R_factor_gt           0.0489
_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^)+(0.0521P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1064
_refine_ls_wR_factor_ref         0.1254
_reflns_number_gt                900
_reflns_number_total             1712
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b206876a.txt
_cod_data_source_block           010523c
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from
2011-04-26.

'_exptl_absorpt_correction_type' value 'MULTI-SCAN'
changed to 'multi-scan' according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 
;
_cod_original_cell_volume        1926.8(9)
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               7114248