Synthesis and Characterization of Dibenzo[a,f]pentalene: Harmonization of the Antiaromatic and Singlet Biradical Character.
Konishi, Akihito; Okada, Yui; Nakano, Motohiro; Sugisaki, Kenji; Sato, Kazunobu; Takui, Takeji; Yasuda, Makoto; Journal of the American Chemical Society 139 (2017) 15284–15287; doi:10.1021/jacs.7b05709

data_4131476
_publ_section_title
;
 Synthesis and Characterization of Dibenzo[a,f]pentalene: Harmonization of
 the Antiaromatic and Singlet Biradical Character.
;
_journal_issue                   43
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              15284
_journal_page_last               15287
_journal_paper_doi               10.1021/jacs.7b05709
_journal_volume                  139
_journal_year                    2017
_chemical_formula_moiety         'C50 H62 Li2 O4'
_chemical_formula_sum            'C50 H62 Li2 O4'
_chemical_formula_weight         740.92
_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
_cell_angle_alpha                90.0000
_cell_angle_beta                 120.3183(14)
_cell_angle_gamma                90.0000
_cell_formula_units_Z            4
_cell_length_a                   24.1978(8)
_cell_length_b                   13.0182(4)
_cell_length_c                   15.5051(6)
_cell_measurement_reflns_used    17012
_cell_measurement_temperature    123
_cell_measurement_theta_max      68.14
_cell_measurement_theta_min      3.30
_cell_volume                     4216.3(3)
_computing_cell_refinement       'RAPID AUTO'
_computing_data_collection       'RAPID AUTO (Rigaku, ????)'
_computing_data_reduction        'RAPID AUTO'
_computing_molecular_graphics    'CrystalStructure 4.2'
_computing_publication_material  'CrystalStructure 4.2 (Rigaku, 2015)'
_computing_structure_refinement  'CRYSTALS (Carruthers, et al., 1999)'
_computing_structure_solution    'SIR92 (Altomare, et al., 1994)'
_diffrn_ambient_temperature      123
_diffrn_detector_area_resol_mean 5.000
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Rigaku R-AXIS RAPID'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54187
_diffrn_reflns_av_R_equivalents  0.0781
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            37761
_diffrn_reflns_theta_full        68.25
_diffrn_reflns_theta_max         68.25
_diffrn_reflns_theta_min         4.001
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.548
_exptl_absorpt_correction_T_max  0.896
_exptl_absorpt_correction_T_min  0.607
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'ABSCOR (Rigaku, 1995)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.167
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1600.00
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.200
_exptl_crystal_size_min          0.200
_refine_diff_density_max         0.376
_refine_diff_density_min         -0.278
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.078
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     285
_refine_ls_number_reflns         2074
_refine_ls_R_factor_gt           0.1013
_refine_ls_shift/su_max          0.015
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
    Chebychev polynomial with 3 parameters (Carruthers & Watkin, 1979)
    15868.0000    22001.8000    6366.7200
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.1367
_reflns_number_gt                1624
_reflns_number_total             3868
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            ja7b05709_si_003.cif
_cod_data_source_block           YO151209
_cod_original_cell_volume        4216.3(2)
_cod_database_code               4131476