Tuning optical properties and local lone-pair off-centering in "hollow" FA<sub>1-<i>x</i></sub> {<i>en</i>} <sub><i>x</i></sub> Pb <sub><i>η</i>-<i>y</i></sub> Sn <sub><i>y</i></sub> Br<sub>3</sub> perovskites.
Balvanz, Adam; Pournara, Anastasia; Reynolds, Robert P.; Meza, Patricia E.; Malliakas, Christos D.; Fletcher, Jared D.; Seshadri, Ram; Dravid, Vinayak P.; Kanatzidis, Mercouri G.; Chemical science 17 (2026) 526–543; doi:10.1039/d5sc01841b

data_1576153
_publ_section_title
;
 Tuning optical properties and local lone-pair off-centering in "hollow"
 FA<sub>1-<i>x</i></sub> {<i>en</i>} <sub><i>x</i></sub> Pb
 <sub><i>&#x3b7;</i>-<i>y</i></sub> Sn <sub><i>y</i></sub> Br<sub>3</sub>
 perovskites.
;
_journal_issue                   1
_journal_name_full               'Chemical science'
_journal_page_first              526
_journal_page_last               543
_journal_paper_doi               10.1039/d5sc01841b
_journal_volume                  17
_journal_year                    2026
_chemical_formula_sum            'C1.226 H5.966 Br3 N2 Pb0.429 Sn0.474'
_chemical_formula_weight         433.6
_space_group_crystal_system      cubic
_space_group_IT_number           221
_space_group_name_Hall           '-P 4 2 3'
_space_group_name_H-M_alt        'P m -3 m'
_symmetry_cell_setting           cubic
_symmetry_Int_Tables_number      221
_symmetry_space_group_name_Hall  '-P 4 2 3'
_symmetry_space_group_name_H-M   'P m -3 m'
_audit_update_record
;
2025-02-21 deposited with the CCDC.	2025-10-21 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            1
_cell_length_a                   6.0236(7)
_cell_length_b                   6.0236(7)
_cell_length_c                   6.0236(7)
_cell_measurement_reflns_used    341
_cell_measurement_temperature    296.52(10)
_cell_measurement_theta_max      25.4
_cell_measurement_theta_min      3.37
_cell_volume                     218.56(4)
_computing_cell_refinement       'CrysAlisPro 1.171.43.70a (Rigaku OD, 2023)'
_computing_data_collection
'CrysAlisPro system (CCD 43.124a 64-bit (release 23-05-2024))'
_computing_data_reduction        'CrysAlisPro 1.171.43.70a (Rigaku OD, 2023)'
_diffrn_ambient_environment      air
_diffrn_ambient_temperature      296.52
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 10.0000
_diffrn_detector_type            HyPix
_diffrn_measured_fraction_theta_full 0.99
_diffrn_measured_fraction_theta_max 0.99
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -92.00 -13.00   0.50   20.00    --  -25.30 -48.00-108.00  158
  2  \w    -42.00 -17.00   0.50   20.00    --   24.67 -88.00 -64.00   50
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type
'XtaLAB Synergy, Single source at offset/far, HyPix'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      -0.0849731000
_diffrn_orient_matrix_UB_12      0.0642829000
_diffrn_orient_matrix_UB_13      -0.0501338000
_diffrn_orient_matrix_UB_21      0.0815466000
_diffrn_orient_matrix_UB_22      0.0660126000
_diffrn_orient_matrix_UB_23      -0.0535091000
_diffrn_orient_matrix_UB_31      -0.0011414000
_diffrn_orient_matrix_UB_32      -0.0733292000
_diffrn_orient_matrix_UB_33      -0.0921026000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0177
_diffrn_reflns_av_sigmaI/netI    0.0265
_diffrn_reflns_av_unetI/netI     0.0127
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            980
_diffrn_reflns_theta_full        37.4
_diffrn_reflns_theta_max         37.4
_diffrn_reflns_theta_min         3.38
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'PhotonJet (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    23.302
_exptl_absorpt_correction_T_max  0.385
_exptl_absorpt_correction_T_min  0.216
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.43.70a (Rigaku Oxford Diffraction, 2023)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    3.2945
_exptl_crystal_description       irregular
_exptl_crystal_F_000             181
_exptl_crystal_size_max          0.125
_exptl_crystal_size_mid          0.066
_exptl_crystal_size_min          0.060
_refine_diff_density_max         1.74
_refine_diff_density_min         -0.51
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_gt    1.71
_refine_ls_goodness_of_fit_ref   1.47
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_constraints    2
_refine_ls_number_parameters     7
_refine_ls_number_reflns         153
_refine_ls_number_restraints     1
_refine_ls_R_factor_all          0.0560
_refine_ls_R_factor_gt           0.0353
_refine_ls_shift/su_max          0.0494
_refine_ls_shift/su_mean         0.0074
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     w=1/(\s^2^(I)+0.0016I^2^)
_refine_ls_weighting_scheme      sigma
_refine_ls_wR_factor_gt          0.0950
_refine_ls_wR_factor_ref         0.1000
_reflns_number_gt                105
_reflns_number_total             153
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            d5sc01841b2.cif
_cod_data_source_block           I_CCDC15
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_diffrn_radiation_probe' value 'X-ray' was changed to
'x-ray' in accordance with the
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

Automatic conversion script
Id: cif_fix_values 8170 2020-07-09 18:12:32Z antanas 

 Adding full bibliography for 1576135--1576153.cif.
;
_cod_original_sg_symbol_Hall     '-P 4;2;3'
_cod_original_sg_symbol_H-M      'P 4/m -3 2/m'
_cod_database_code               1576153
_chemical_oxdiff_formula         'Pb0.5 Sn0.5 Br3'
_chemical_oxdiff_usercomment     (3AMP)(EA)Pb2I7
_reflns_odcompleteness_completeness 100.00
_reflns_odcompleteness_theta     36.23
_reflns_odcompleteness_iscentric 1
_oxdiff_exptl_absorpt_empirical_full_min 0.778
_oxdiff_exptl_absorpt_empirical_full_max 1.267
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;