Two metal-free perovskite molecules with different 3D frameworks show reversible phase transition, dielectric anomaly and SHG effect.
Zhang, Haina; You, Xiuli; Zhang, Mengxia; Guo, Wenjing; Wei, Zhenhong; Cai, Hu; Dalton transactions (Cambridge, England : 2003) 52 (2023) 1753–1760; doi:10.1039/d2dt03889g

data_7712064
_publ_section_title
;
 Two metal-free perovskite molecules with different 3D frameworks show
 reversible phase transition, dielectric anomaly and SHG effect.
;
_journal_issue                   6
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              1753
_journal_page_last               1760
_journal_paper_doi               10.1039/d2dt03889g
_journal_volume                  52
_journal_year                    2023
_chemical_formula_sum            'C9 I3 N'
_chemical_formula_weight         502.80
_space_group_IT_number           166
_space_group_name_Hall           '-R 3 2"'
_space_group_name_H-M_alt        'R -3 m :H'
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_H-M   'R -3 m :H'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2022-11-16 deposited with the CCDC.	2023-01-06 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                120.00
_cell_formula_units_Z            3
_cell_length_a                   10.2423(12)
_cell_length_b                   10.2423(12)
_cell_length_c                   12.5442(14)
_cell_measurement_reflns_used    604
_cell_measurement_temperature    330(2)
_cell_measurement_theta_max      71.0560
_cell_measurement_theta_min      6.0620
_cell_volume                     1139.6(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      330(2)
_diffrn_measured_fraction_theta_full 0.928
_diffrn_measured_fraction_theta_max 0.928
_diffrn_measurement_device_type  'multiwire proportional'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.1551
_diffrn_reflns_av_sigmaI/netI    0.0515
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            1532
_diffrn_reflns_theta_full        75.87
_diffrn_reflns_theta_max         75.87
_diffrn_reflns_theta_min         6.11
_exptl_absorpt_coefficient_mu    48.196
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    2.198
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             660
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.811
_refine_diff_density_min         -2.268
_refine_diff_density_rms         0.330
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.006
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     16
_refine_ls_number_reflns         295
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.007
_refine_ls_R_factor_all          0.1414
_refine_ls_R_factor_gt           0.1211
_refine_ls_shift/su_max          0.197
_refine_ls_shift/su_mean         0.056
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1993P)^2^+13.7531P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2973
_refine_ls_wR_factor_ref         0.3265
_reflns_number_gt                212
_reflns_number_total             295
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            d2dt03889g2.cif
_cod_data_source_block           bak_CCDC1
_cod_depositor_comments
'Adding full bibliography for 7712063--7712066.cif.'
_cod_original_sg_symbol_H-M      R-3m
_cod_database_code               7712064