A Multiaxial Layered Halide Double Perovskite Ferroelectric with Multiple Ferroic Orders
Liu, Xitao; Xu, Zhiyun; Long, Peiqing; Yao, Yunpeng; Ji, Chengmin; Li, Lina; Sun, Zhihua; Hong, Maochun; Luo, Junhua; Chemistry of Materials  (2020) –; doi:10.1021/acs.chemmater.0c02966

data_4003693
_publ_section_title
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 A Multiaxial Layered Halide Double Perovskite Ferroelectric with Multiple
 Ferroic Orders
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_journal_name_full               'Chemistry of Materials'
_journal_paper_doi               10.1021/acs.chemmater.0c02966
_journal_year                    2020
_chemical_formula_moiety         '2(Ag0.5 Bi0.5 Br3.5 Cs0.5), 2(C4 H12 N)'
_chemical_formula_sum            'C8 H24 Ag Bi Br7 Cs N2'
_chemical_formula_weight         1157.42
_space_group_crystal_system      tetragonal
_space_group_IT_number           139
_space_group_name_Hall           '-I 4 2'
_space_group_name_H-M_alt        'I 4/m m m'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_date             2019-10-19
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   5.7059(5)
_cell_length_b                   5.7059(5)
_cell_length_c                   40.293(6)
_cell_measurement_reflns_used    1106
_cell_measurement_temperature    400(2)
_cell_measurement_theta_max      26.703
_cell_measurement_theta_min      2.720
_cell_volume                     1311.8(3)
_computing_cell_refinement       'SAINT V8.38A (?, 2016)'
_computing_data_reduction        'SAINT V8.38A (?, 2016)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'XS (Sheldrick, 2008)'
_diffrn_ambient_temperature      400.15
_diffrn_detector                 'Bruker APEX3 area detector'
_diffrn_detector_area_resol_mean 7.9
_diffrn_detector_type            'CCD area detector'
_diffrn_measured_fraction_theta_full 0.983
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device       'three-circle diffractometer'
_diffrn_measurement_device_type  'Bruker SMART APEX3 area detector'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  'mirror optics'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0542
_diffrn_reflns_av_unetI/netI     0.0292
_diffrn_reflns_Laue_measured_fraction_full 0.983
_diffrn_reflns_Laue_measured_fraction_max 0.987
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       52
_diffrn_reflns_limit_l_min       -50
_diffrn_reflns_number            3847
_diffrn_reflns_point_group_measured_fraction_full 0.983
_diffrn_reflns_point_group_measured_fraction_max 0.987
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.497
_diffrn_reflns_theta_min         3.606
_diffrn_source                   'microfocus sealed X-ray tube'
_diffrn_source_type              'Incoatec I\ms'
_exptl_absorpt_coefficient_mu    19.467
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.3802
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1275 before and 0.0548 after correction.
The Ratio of minimum to maximum transmission is 0.5099.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            brown
_exptl_crystal_colour_primary    brown
_exptl_crystal_density_diffrn    2.930
_exptl_crystal_description       block
_exptl_crystal_F_000             1032
_exptl_crystal_size_max          0.05
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.03
_refine_diff_density_max         2.420
_refine_diff_density_min         -1.389
_refine_diff_density_rms         0.195
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.094
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     62
_refine_ls_number_reflns         522
_refine_ls_number_restraints     61
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0835
_refine_ls_R_factor_gt           0.0545
_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^)+(0.0918P)^2^+12.6715P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1524
_refine_ls_wR_factor_ref         0.1703
_reflns_Friedel_coverage         0.000
_reflns_number_gt                360
_reflns_number_total             522
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            cm0c02966_si_004.cif
_cod_data_source_block           x1_pl
_cod_database_code               4003693
_shelx_shelxl_version_number     2018/3
_olex2_refinement_description
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1. Fixed Uiso
 At 1.2 times of:
  All C(H,H) groups, All N(H,H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Shared sites
{Ag1, Bi1}
3. Restrained distances
 C3-C2 = C3-C4 = C2-C1
 1.5 with sigma of 0.02
 C1-N1
 1.47 with sigma of 0.02
 N1-Br2
 3.35 with sigma of 0.02
 C1-C3
 2.3 with sigma of 0.04
 C4-C2
 2.3 with sigma of 0.04
4. Uiso/Uaniso restraints and constraints
C1 \\sim C2 \\sim C3 \\sim C4 \\sim N1: within 2A with sigma of 0.01 and sigma
for terminal atoms of 0.02
Uanis(C1) \\sim Ueq, Uanis(C2) \\sim Ueq, Uanis(C3) \\sim Ueq, Uanis(C4) \\sim
Ueq, Uanis(N1) \\sim Ueq: with sigma of 0.001 and sigma for terminal atoms of
0.002
Uanis(Ag1) = Uanis(Bi1)
5. Others
 Fixed Sof: Bi1(0.0625) Ag1(0.0625) N1(0.125) H1A(0.125) H1B(0.125) H1C(0.125)
 C1(0.125) H1D(0.125) H1E(0.125) C2(0.125) H2A(0.125) H2B(0.125) C3(0.125)
 H3A(0.125) H3B(0.125) C4(0.125) H4A(0.125) H4B(0.125) H4C(0.125)
6.a Secondary CH2 refined with riding coordinates:
 C1(H1D,H1E), C2(H2A,H2B), C3(H3A,H3B)
6.b Idealised Me refined as rotating group:
 N1(H1A,H1B,H1C), C4(H4A,H4B,H4C)
;
_olex2_submission_special_instructions 'No special instructions were received'