Confinement-Driven Ferroelectricity in a Two-Dimensional Hybrid Lead Iodide Perovskite.
Chen, Xiao-Gang; Song, Xian-Jiang; Zhang, Zhi-Xu; Zhang, Han-Yue; Pan, Qiang; Yao, Jie; You, Yu-Meng; Xiong, Ren-Gen; Journal of the American Chemical Society 142 (2020) 10212–10218; doi:10.1021/jacs.0c03710

data_4134988
_publ_section_title
;
 Confinement-Driven Ferroelectricity in a Two-Dimensional Hybrid Lead
 Iodide Perovskite.
;
_journal_issue                   22
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              10212
_journal_page_last               10218
_journal_paper_doi               10.1021/jacs.0c03710
_journal_volume                  142
_journal_year                    2020
_chemical_formula_moiety         'I3 Pb, C6 H14 N'
_chemical_formula_sum            'C6 H14 I3 N Pb'
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_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
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_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_k_min       -24
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_diffrn_reflns_limit_l_min       -11
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_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.796
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_diffrn_reflns_theta_max         30.652
_diffrn_reflns_theta_min         2.562
_diffrn_source                   'Rotating-anode X-ray tube'
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_exptl_absorpt_correction_T_max  0.016
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_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            yellow
_exptl_crystal_density_diffrn    3.357
_exptl_crystal_description       prism
_exptl_crystal_F_000             1174.25
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.22
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_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'
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_refine_ls_number_reflns         1214
_refine_ls_number_restraints     47
_refine_ls_restrained_S_all      0.962
_refine_ls_R_factor_all          0.0545
_refine_ls_R_factor_gt           0.0380
_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^)+(0.0716P)^2^+5.0191P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1035
_refine_ls_wR_factor_ref         0.1111
_reflns_Friedel_coverage         0.000
_reflns_number_gt                732
_reflns_number_total             1214
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja0c03710_si_005.cif
_cod_data_source_block           CMCM
_cod_depositor_comments
;Adding full bibliography for 4134988--4134996.cif.

 Adding full bibliography for 4134988--4134996.cif.
;
_cod_database_code               4134988
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              22393
_shelx_hkl_checksum              72855