Observation of vortex domains in a two-dimensional lead iodide perovskite ferroelectric.
Zhang, Han-Yue; Song, Xian-Jiang; Chen, Xiao-Gang; Zhang, Zhi-Xu; You, Yu-Meng; Tang, Yuan-Yuan; Xiong, Ren-Gen; Journal of the American Chemical Society  (2020) –; doi:10.1021/jacs.0c00371

data_4134273
_publ_section_title
;
 Observation of vortex domains in a two-dimensional lead iodide perovskite
 ferroelectric.
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_paper_doi               10.1021/jacs.0c00371
_journal_year                    2020
_chemical_formula_moiety         'I4 Pb, 2(C5 H10 F2 N)'
_chemical_formula_sum            'C10 H20 F4 I4 N2 Pb'
_chemical_formula_weight         959.08
_space_group_crystal_system      orthorhombic
_space_group_IT_number           41
_space_group_name_Hall           'A 2 -2ab'
_space_group_name_H-M_alt        'A e a 2'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   9.2974(3)
_cell_length_b                   25.1758(7)
_cell_length_c                   8.9611(3)
_cell_measurement_reflns_used    4911
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      30.7770
_cell_measurement_theta_min      2.7160
_cell_volume                     2097.52(11)
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'XtaLAB Synergy R, DW system, HyPix'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0521
_diffrn_reflns_av_unetI/netI     0.0409
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       29
_diffrn_reflns_limit_k_min       -27
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            4438
_diffrn_reflns_point_group_measured_fraction_full 0.903
_diffrn_reflns_point_group_measured_fraction_max 0.903
_diffrn_reflns_theta_full        24.996
_diffrn_reflns_theta_max         24.996
_diffrn_reflns_theta_min         2.724
_diffrn_source                   'Rotating-anode X-ray tube'
_exptl_absorpt_coefficient_mu    13.958
_exptl_absorpt_correction_T_max  0.04
_exptl_absorpt_correction_T_min  0.021
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.40.14e (Rigaku Oxford Diffraction, 2018)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    3.037
_exptl_crystal_description       sheet
_exptl_crystal_F_000             1696
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.23
_refine_diff_density_max         1.494
_refine_diff_density_min         -2.521
_refine_diff_density_rms         0.259
_refine_ls_abs_structure_details
;
 Classical Flack method preferred over Parsons because s.u. lower.
;
_refine_ls_abs_structure_Flack   0.013(6)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.053
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     96
_refine_ls_number_reflns         1673
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.052
_refine_ls_R_factor_all          0.0355
_refine_ls_R_factor_gt           0.0351
_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^)+(0.0631P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0847
_refine_ls_wR_factor_ref         0.0849
_reflns_Friedel_coverage         0.685
_reflns_Friedel_fraction_full    0.792
_reflns_Friedel_fraction_max     0.792
_reflns_number_gt                1644
_reflns_number_total             1851
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja0c00371_si_009.cif
_cod_data_source_block           ABA2
_cod_original_sg_symbol_Hall     'A 2 -2ac'
_cod_original_sg_symbol_H-M      'A b a 2'
_cod_database_code               4134273
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              33888
_shelx_hkl_checksum              22506