Large Electrostrictive Coefficient in a Two-Dimensional Hybrid Perovskite Ferroelectric.
Zhang, Han-Yue; Zhang, Zhi-Xu; Chen, Xiao-Gang; Song, Xian-Jiang; Zhang, Yi; Xiong, Ren-Gen; Journal of the American Chemical Society 143 (2021) 1664–1672; doi:10.1021/jacs.0c12907

data_4135513
_publ_section_title
;
 Large Electrostrictive Coefficient in a Two-Dimensional Hybrid Perovskite
 Ferroelectric.
;
_journal_issue                   3
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              1664
_journal_page_last               1672
_journal_paper_doi               10.1021/jacs.0c12907
_journal_volume                  143
_journal_year                    2021
_chemical_formula_moiety         'Br4 Pb, C5 H16 N P '
_chemical_formula_sum            'C5 H16 Br4 N P Pb'
_chemical_formula_weight         647.96
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90.145(4)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   6.0177(3)
_cell_length_b                   12.0789(5)
_cell_length_c                   9.9796(4)
_cell_measurement_reflns_used    4860
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      31.5720
_cell_measurement_theta_min      2.0300
_cell_volume                     725.39(6)
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.990
_diffrn_measurement_device_type  'XtaLAB Synergy R, HyPix'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0569
_diffrn_reflns_av_unetI/netI     0.0522
_diffrn_reflns_Laue_measured_fraction_full 0.990
_diffrn_reflns_Laue_measured_fraction_max 0.990
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            4964
_diffrn_reflns_point_group_measured_fraction_full 0.922
_diffrn_reflns_point_group_measured_fraction_max 0.922
_diffrn_reflns_theta_full        24.999
_diffrn_reflns_theta_max         24.999
_diffrn_reflns_theta_min         2.041
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    22.718
_exptl_absorpt_correction_T_max  0.003
_exptl_absorpt_correction_T_min  0.002
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.40.39a (Rigaku Oxford Diffraction, 2019)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    2.967
_exptl_crystal_description       sheet
_exptl_crystal_F_000             580
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.26
_refine_diff_density_max         3.918
_refine_diff_density_min         -2.336
_refine_diff_density_rms         0.429
_refine_ls_abs_structure_details
;
 Flack x determined using 888 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.03(2)
_refine_ls_extinction_coef       0.0350(5)
_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   1.074
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     86
_refine_ls_number_reflns         2341
_refine_ls_number_restraints     74
_refine_ls_restrained_S_all      1.060
_refine_ls_R_factor_all          0.0694
_refine_ls_R_factor_gt           0.0679
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0905P)^2^+39.1359P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1764
_refine_ls_wR_factor_ref         0.1774
_reflns_Friedel_coverage         0.771
_reflns_Friedel_fraction_full    0.847
_reflns_Friedel_fraction_max     0.847
_reflns_number_gt                2265
_reflns_number_total             2341
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja0c12907_si_003.cif
_cod_data_source_block           P21
_cod_depositor_comments
'Adding full bibliography for 4135512--4135514.cif.'
_cod_original_sg_symbol_H-M      'P 21'
_cod_original_formula_sum        'C5 H16 Br4 N P Pb '
_cod_database_code               4135513
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              73052
_shelx_hkl_checksum              72070