Quantum ferroelectricity in charge-transfer complex crystals
Sachio Horiuchi; Kensuke Kobayashi; Reiji Kumai; Nao Minami; Fumitaka Kagawa; Yoshinori Tokura; Nature Communications 6 (2015) 7469–; doi:10.1038/ncomms8469

data_1548230
_publ_section_title
;
 Quantum ferroelectricity in charge-transfer complex crystals
;
_journal_name_full               'Nature Communications'
_journal_page_first              7469
_journal_paper_doi               10.1038/ncomms8469
_journal_volume                  6
_journal_year                    2015
_chemical_formula_moiety         'C12 H4 Br2 I2 O2 S4 '
_chemical_formula_sum            'C12 H4 Br2 I2 O2 S4'
_chemical_formula_weight         722.02
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_Int_Tables_number      2
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_cell_angle_alpha                111.669(10)
_cell_angle_beta                 108.287(7)
_cell_angle_gamma                93.393(10)
_cell_formula_units_Z            1
_cell_length_a                   7.008(2)
_cell_length_b                   7.571(2)
_cell_length_c                   9.696(3)
_cell_measurement_reflns_used    8455
_cell_measurement_temperature    300(1)
_cell_measurement_theta_max      39.6
_cell_measurement_theta_min      2.4
_cell_volume                     444.9(2)
_computing_cell_refinement       PROCESS-AUTO
_computing_data_collection       PROCESS-AUTO
_computing_data_reduction        CrystalStructure
_computing_publication_material  'CrystalStructure 3.8'
_computing_structure_refinement  CRYSTALS
_computing_structure_solution    SIR2004
_diffrn_ambient_temperature      300(1)
_diffrn_measured_fraction_theta_full 0.519
_diffrn_measured_fraction_theta_max 0.519
_diffrn_measurement_device_type  Rigaku_IPDSC
_diffrn_measurement_method       IP
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.68888
_diffrn_reflns_av_R_equivalents  0.031
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            9351
_diffrn_reflns_theta_full        39.59
_diffrn_reflns_theta_max         39.59
_exptl_absorpt_coefficient_mu    7.723
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.730
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    2.694
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             332.00
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.63
_refine_diff_density_min         -2.58
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.975
_refine_ls_hydrogen_treatment    refall
_refine_ls_number_parameters     108
_refine_ls_number_reflns         2109
_refine_ls_R_factor_gt           0.0365
_refine_ls_shift/su_max          0.0000
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details
;
    Chebychev polynomial with 3 parameters (Carruthers & Watkin, 1979)
    6.1007    1.2524    5.0503
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.0398
_reflns_number_gt                2098
_reflns_number_total             3059
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            ncomms8469-s3.cif
_cod_data_source_block           '_TTF-25QBr2I2_300K'
_cod_original_cell_volume        445.0(2)
_cod_original_formula_sum        'C12 H4 Br2 I2 O2 S4 '
_cod_database_code               1548230