Biradicaloid Behavior of a Twisted Double Bond.
Hamamoto, Yosuke; Hirao, Yasukazu; Kubo, Takashi; The journal of physical chemistry letters 12 (2021) 4729–4734; doi:10.1021/acs.jpclett.1c00664

data_8000496
_publ_section_title
;
 Biradicaloid Behavior of a Twisted Double Bond.
;
_journal_issue                   19
_journal_name_full               'The journal of physical chemistry letters'
_journal_page_first              4729
_journal_page_last               4734
_journal_paper_doi               10.1021/acs.jpclett.1c00664
_journal_volume                  12
_journal_year                    2021
_chemical_formula_sum            'C32 H24 O6'
_chemical_formula_weight         504.51
_chemical_name_common            3,3',6,6'-tetramethoxybianthrone
_chemical_name_systematic
;
3,3',6,6'-tetramethoxy-10H,10'H-[9,9'-bianthracenylidene]-10,10'-dione
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2016/6
_cell_angle_alpha                90
_cell_angle_beta                 107.103(8)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.5969(5)
_cell_length_b                   13.4458(6)
_cell_length_c                   15.9778(9)
_cell_measurement_reflns_used    9036
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27.46
_cell_measurement_theta_min      2.38
_cell_volume                     2381.2(2)
_computing_cell_refinement       'RAPID AUTO'
_computing_data_collection       'RAPID AUTO (Rigaku, ????)'
_computing_data_reduction        'RAPID AUTO'
_computing_molecular_graphics
;
Yadokari-XG 2009 (K. Wakita, T. Nemoto, et al., 2009)
;
_computing_publication_material
;
Yadokari-XG 2009 (K. Wakita, T. Nemoto, et al., 2009)
;
_computing_structure_refinement  'SHELXL-2016/6 (Sheldrick, 2016)'
_computing_structure_solution    Sir2014
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type
;
Rigaku MicroMax-007HF,VariMax-Mo and RAPID II
;
_diffrn_measurement_method       \w
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0217
_diffrn_reflns_av_unetI/netI     0.0191
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            11314
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.458
_diffrn_reflns_theta_min         2.381
_diffrn_source                   'micro-focus rotating anode'
_exptl_absorpt_coefficient_mu    0.097
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.8348
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
Empirical Absorption Correction   March 2001 T. Higashi
    Rigaku Corporation, Tokyo, Japan
;
_exptl_crystal_colour            Yellow
_exptl_crystal_density_diffrn    1.407
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Platelet
_exptl_crystal_F_000             1056
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.200
_exptl_crystal_size_min          0.020
_refine_diff_density_max         0.315
_refine_diff_density_min         -0.142
_refine_diff_density_rms         0.047
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     174
_refine_ls_number_reflns         2727
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0533
_refine_ls_R_factor_gt           0.0399
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0570P)^2^+1.3489P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1003
_refine_ls_wR_factor_ref         0.1070
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2179
_reflns_number_total             2727
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jz1c00664_si_002.cif
_cod_data_source_block           BA2-Folded
_cod_depositor_comments
'Adding full bibliography for 8000496--8000497.cif.'
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               8000496
_shelx_shelxl_version_number     2016/6
_shelx_estimated_absorpt_t_min   0.981
_shelx_estimated_absorpt_t_max   0.998
_shelx_res_checksum              68808
_shelx_hkl_checksum              91316