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_4135514
_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                 90.154(5)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   6.0691(4)
_cell_length_b                   12.1645(6)
_cell_length_c                   10.0438(5)
_cell_measurement_reflns_used    3644
_cell_measurement_temperature    448(2)
_cell_measurement_theta_max      29.6370
_cell_measurement_theta_min      2.0070
_cell_volume                     741.51(7)
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      448(2)
_diffrn_measured_fraction_theta_full 0.963
_diffrn_measured_fraction_theta_max 0.802
_diffrn_measurement_device_type  'XtaLAB Synergy R, HyPix'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0562
_diffrn_reflns_av_unetI/netI     0.0727
_diffrn_reflns_Laue_measured_fraction_full 0.963
_diffrn_reflns_Laue_measured_fraction_max 0.802
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            6687
_diffrn_reflns_point_group_measured_fraction_full 0.971
_diffrn_reflns_point_group_measured_fraction_max 0.806
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         31.716
_diffrn_reflns_theta_min         2.028
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    22.224
_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    2.902
_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         4.175
_refine_diff_density_min         -5.692
_refine_diff_density_rms         0.735
_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   0.09(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.017
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     104
_refine_ls_number_reflns         3474
_refine_ls_number_restraints     86
_refine_ls_restrained_S_all      1.012
_refine_ls_R_factor_all          0.0963
_refine_ls_R_factor_gt           0.0823
_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^)+(0.1563P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2139
_refine_ls_wR_factor_ref         0.2206
_reflns_Friedel_coverage         0.931
_reflns_Friedel_fraction_full    0.980
_reflns_Friedel_fraction_max     0.811
_reflns_number_gt                2745
_reflns_number_total             3474
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja0c12907_si_004.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               4135514
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              87688
_shelx_hkl_checksum              38725