A helically-twisted ladder based on 9,9′-bifluorenylidene: synthesis, characterization, and carrier-transport properties
Xu, Jinjia; Takai, Atsuro; Bannaron, Alisa; Nakagawa, Takafumi; Matsuo, Yutaka; Sugimoto, Manabu; Matsushita, Yoshitaka; Takeuchi, Masayuki; Materials Chemistry Frontiers 2 (2018) 780–; doi:10.1039/C7QM00583K

data_1553717
_publ_section_title
;
 A helically-twisted ladder based on 9,9&#x2032;-bifluorenylidene:
 synthesis, characterization, and carrier-transport properties
;
_journal_issue                   4
_journal_name_full               'Materials Chemistry Frontiers'
_journal_page_first              780
_journal_paper_doi               10.1039/C7QM00583K
_journal_volume                  2
_journal_year                    2018
_chemical_formula_sum            'C13 H7'
_chemical_formula_weight         163.19
_chemical_name_common            CBF
_chemical_name_systematic        '9,9'-bifluorenylidene cyclic dimer'
_space_group_crystal_system      tetragonal
_space_group_IT_number           116
_space_group_name_Hall           'P -4 -2c'
_space_group_name_H-M_alt        'P -4 c 2'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2017-12-11 deposited with the CCDC.
2018-01-26 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   14.367(4)
_cell_length_b                   14.367(4)
_cell_length_c                   7.992(3)
_cell_measurement_reflns_used    2927
_cell_measurement_temperature    213(2)
_cell_measurement_theta_max      20.90
_cell_measurement_theta_min      2.84
_cell_volume                     1649.6(9)
_computing_cell_refinement       'CrystalClear (Rigaku, 1997--2002)'
_computing_data_collection       'CrystalClear (Rigaku, 1997--2002)'
_computing_data_reduction        'CrystalClear (Rigaku, 1997--2002)'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT (Sheldrick, 2014)'
_diffrn_ambient_temperature      213(2)
_diffrn_detector_area_resol_mean 28.5714
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device
;
Rigaku AFC11 Saturn724+ (4x4 bin mode)
;
_diffrn_measurement_method       dtprofit.ref
_diffrn_radiation_detector       CCD
_diffrn_radiation_monochromator  Confocal
_diffrn_radiation_source         'Rotating Anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0371
_diffrn_reflns_av_unetI/netI     0.0231
_diffrn_reflns_Laue_measured_fraction_full 0.992
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            5308
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        21.000
_diffrn_reflns_theta_max         21.000
_diffrn_reflns_theta_min         2.835
_exptl_absorpt_coefficient_mu    0.075
_exptl_absorpt_correction_T_max  0.4876
_exptl_absorpt_correction_T_min  0.3772
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrystalClear (Rigaku, 1997--2002)
;
_exptl_crystal_colour            Orange
_exptl_crystal_density_diffrn    1.314
_exptl_crystal_description       Bar
_exptl_crystal_F_000             680
_exptl_crystal_recrystallization_method 'Vapour deposition'
_exptl_crystal_size_max          0.409
_exptl_crystal_size_mid          0.045
_exptl_crystal_size_min          0.045
_refine_diff_density_max         0.135
_refine_diff_density_min         -0.146
_refine_diff_density_rms         0.033
_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   -3(10)
_refine_ls_extinction_coef       0.026(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   1.299
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     120
_refine_ls_number_reflns         886
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.299
_refine_ls_R_factor_all          0.0488
_refine_ls_R_factor_gt           0.0469
_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^)+(0.0160P)^2^+1.4636P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1059
_refine_ls_wR_factor_ref         0.1067
_reflns_Friedel_coverage         0.709
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                859
_reflns_number_total             886
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c7qm00583k2.cif
_cod_data_source_block           shelx
_cod_original_cell_volume        1649.6(11)
_cod_database_code               1553717
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.970
_shelx_estimated_absorpt_t_max   0.997
_shelx_res_checksum              79264
_shelx_hkl_checksum              581