Fluoreno[4,3-c]fluorene: A Closed-Shell, Fully Conjugated Hydrocarbon.
Rose, Bradley D.; Vonnegut, Chris L.; Zakharov, Lev N.; Haley, Michael M.; Organic letters 14 (2012) 2426–2429; doi:10.1021/ol300942z

data_1507646
_publ_section_title
;
 Fluoreno[4,3-c]fluorene: A Closed-Shell, Fully Conjugated Hydrocarbon.
;
_journal_issue                   9
_journal_name_full               'Organic letters'
_journal_page_first              2426
_journal_page_last               2429
_journal_paper_doi               10.1021/ol300942z
_journal_volume                  14
_journal_year                    2012
_chemical_formula_sum            'C56 H56'
_chemical_formula_weight         729.01
_chemical_name_systematic
;
 ?
;
_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           SHELXLTL
_cell_angle_alpha                90.00
_cell_angle_beta                 99.66(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   26.50(3)
_cell_length_b                   14.575(18)
_cell_length_c                   11.213(14)
_cell_measurement_reflns_used    500
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      18.59
_cell_measurement_theta_min      2.34
_cell_volume                     4269(9)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker Apex 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  0.1224
_diffrn_reflns_av_sigmaI/netI    0.1185
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            12304
_diffrn_reflns_theta_full        23.41
_diffrn_reflns_theta_max         23.41
_diffrn_reflns_theta_min         1.56
_exptl_absorpt_coefficient_mu    0.064
_exptl_absorpt_correction_T_max  0.9987
_exptl_absorpt_correction_T_min  0.9899
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            dark-blue
_exptl_crystal_density_diffrn    1.134
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1568
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.230
_refine_diff_density_min         -0.251
_refine_diff_density_rms         0.046
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.022
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     254
_refine_ls_number_reflns         3118
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.022
_refine_ls_R_factor_all          0.1696
_refine_ls_R_factor_gt           0.0812
_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^)+(0.0814P)^2^+2.2671P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1665
_refine_ls_wR_factor_ref         0.2101
_reflns_number_gt                1615
_reflns_number_total             3118
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol300942z_si_002.cif
_cod_data_source_block           mh83
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               1507646