An Unprecedented Biaxial Trilayered Hybrid Perovskite Ferroelectric with Directionally Tunable Photovoltaic Effects.
Wang, Sasa; Liu, Xitao; Li, Lina; Ji, Chengmin; Sun, Zhihua; Wu, Zhenyue; Hong, Maochun; Luo, Junhua; Journal of the American Chemical Society 141 (2019) 7693–7697; doi:10.1021/jacs.9b02558

data_4127236
_publ_section_title
;
 An Unprecedented Biaxial Trilayered Hybrid Perovskite Ferroelectric with
 Directionally Tunable Photovoltaic Effects.
;
_journal_issue                   19
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              7693
_journal_page_last               7697
_journal_paper_doi               10.1021/jacs.9b02558
_journal_volume                  141
_journal_year                    2019
_chemical_formula_sum            'C8 H32 Br10 N4 Pb3'
_chemical_formula_weight         1605.05
_space_group_IT_number           41
_space_group_name_Hall           'C -2ac 2'
_space_group_name_H-M_alt        'C 2 e b'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'C -2ac 2'
_symmetry_space_group_name_H-M   'C 2 e b'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.4247(3)
_cell_length_b                   46.305(3)
_cell_length_c                   8.4256(3)
_cell_measurement_reflns_used    2214
_cell_measurement_temperature    280(2)
_cell_measurement_theta_max      27.42
_cell_measurement_theta_min      2.64
_cell_volume                     3286.9(3)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      280(2)
_diffrn_measured_fraction_theta_full 0.980
_diffrn_measured_fraction_theta_max 0.980
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w 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  0.0558
_diffrn_reflns_av_sigmaI/netI    0.0611
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       54
_diffrn_reflns_limit_k_min       -54
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            9290
_diffrn_reflns_theta_full        25.02
_diffrn_reflns_theta_max         25.02
_diffrn_reflns_theta_min         2.57
_exptl_absorpt_coefficient_mu    27.490
_exptl_crystal_density_diffrn    3.243
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       yellow
_exptl_crystal_F_000             2816
_refine_diff_density_max         4.402
_refine_diff_density_min         -3.762
_refine_diff_density_rms         0.553
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.00
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.113
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     118
_refine_ls_number_reflns         2525
_refine_ls_number_restraints     71
_refine_ls_restrained_S_all      1.098
_refine_ls_R_factor_all          0.1602
_refine_ls_R_factor_gt           0.1094
_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^)+(0.0000P)^2^+1349.6768P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1926
_refine_ls_wR_factor_ref         0.2189
_reflns_number_gt                1660
_reflns_number_total             2525
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja9b02558_si_002.cif
_cod_data_source_block           c:\users\dell\desktop\1\autost~1\2
_cod_depositor_comments
'Adding full bibliography for 4127235--4127236.cif.'
_cod_original_cell_volume        3286.9(2)
_cod_original_sg_symbol_H-M      C2cb
_cod_database_code               4127236