Ba4Ge2Sb2Te8Se2 and Ba2Ge2Te4.5Se0.5: complex heteroanionic Ge-containing phases with extremely low thermal conductivities
Yadav, Sweta; Swati,; Prakash, Jai; New Journal of Chemistry 49 (2025) 14131–14141; doi:10.1039/D5NJ01642H

data_7063928
_publ_section_title
;
 Ba4Ge2Sb2Te8Se2 and Ba2Ge2Te4.5Se0.5: complex heteroanionic Ge-containing
 phases with extremely low thermal conductivities
;
_journal_issue                   33
_journal_name_full               'New Journal of Chemistry'
_journal_page_first              14131
_journal_page_last               14141
_journal_paper_doi               10.1039/D5NJ01642H
_journal_volume                  49
_journal_year                    2025
_chemical_formula_sum            'Ba2 Ge2 Se0.5 Te4.5'
_chemical_formula_weight         1033.66
_space_group_crystal_system      orthorhombic
_space_group_IT_number           33
_space_group_name_Hall           'P 2c -2n'
_space_group_name_H-M_alt        'P n a 21'
_audit_creation_method           SHELXL-2017/1
_audit_update_record
;
2025-06-27 deposited with the CCDC.	2025-07-17 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   13.2860(7)
_cell_length_b                   9.0973(6)
_cell_length_c                   9.8653(5)
_cell_measurement_reflns_used    16596
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      30.2
_cell_measurement_theta_min      3.1
_cell_volume                     1192.39(12)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2017/1 (Sheldrick, 2017)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0599
_diffrn_reflns_av_unetI/netI     0.0521
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            16596
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.992
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.521
_diffrn_reflns_theta_min         2.714
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    23.761
_exptl_absorpt_correction_T_max  0.7461
_exptl_absorpt_correction_T_min  0.3500
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   multi-scan
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    5.758
_exptl_crystal_description       block
_exptl_crystal_F_000             1708
_exptl_crystal_size_max          0.07
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.05
_refine_diff_density_max         1.114
_refine_diff_density_min         -1.021
_refine_diff_density_rms         0.261
_refine_ls_abs_structure_details
;
 Flack x determined using 1370 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.04(2)
_refine_ls_extinction_coef       0.00056(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2017/1 (Sheldrick 2017)'
_refine_ls_goodness_of_fit_ref   1.038
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     84
_refine_ls_number_reflns         3600
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.038
_refine_ls_R_factor_all          0.0338
_refine_ls_R_factor_gt           0.0278
_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^)] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0466
_refine_ls_wR_factor_ref         0.0481
_reflns_Friedel_coverage         0.884
_reflns_Friedel_fraction_full    0.993
_reflns_Friedel_fraction_max     0.983
_reflns_number_gt                3289
_reflns_number_total             3600
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5nj01642h2.cif
_cod_data_source_block           BaGeTeSe
_cod_depositor_comments
'Adding full bibliography for 7063926--7063929.cif.'
_cod_original_formula_sum        'Ba2 Ge2 Se0.50 Te4.50'
_cod_database_code               7063928
_shelx_shelxl_version_number     2017/1
_exptl_absorpt_special_details   SADABS-2016/2
_shelx_res_checksum              22922