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_7063929
_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            'Ba4 Ge2 Sb2 Se1.79 Te8.21'
_chemical_formula_weight         2126.85
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_audit_creation_method           SHELXL-2019/1
_audit_update_record
;
2025-06-25 deposited with the CCDC.	2025-07-17 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90.106(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   13.3789(8)
_cell_length_b                   13.2844(8)
_cell_length_c                   13.8394(8)
_cell_measurement_reflns_used    61509
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      28.3
_cell_measurement_theta_min      2.1
_cell_volume                     2459.7(3)
_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-2019/1 (Sheldrick, 2019)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.996
_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  0.0510
_diffrn_reflns_av_unetI/netI     0.0234
_diffrn_reflns_Laue_measured_fraction_full 0.995
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            61478
_diffrn_reflns_point_group_measured_fraction_full 0.995
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.282
_diffrn_reflns_theta_min         2.125
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    23.043
_exptl_absorpt_correction_T_max  0.7461
_exptl_absorpt_correction_T_min  0.4066
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   multi-scan
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    5.743
_exptl_crystal_description       block
_exptl_crystal_F_000             3511
_exptl_crystal_size_max          0.079
_exptl_crystal_size_mid          0.071
_exptl_crystal_size_min          0.065
_refine_diff_density_max         3.437
_refine_diff_density_min         -1.847
_refine_diff_density_rms         0.461
_refine_ls_extinction_coef       0.00072(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2019/1 (Sheldrick 2019)'
_refine_ls_goodness_of_fit_ref   1.209
_refine_ls_hydrogen_treatment    undef
_refine_ls_matrix_type           full
_refine_ls_number_parameters     169
_refine_ls_number_reflns         6074
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.209
_refine_ls_R_factor_all          0.0425
_refine_ls_R_factor_gt           0.0396
_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^)+(0.0381P)^2^+110.7622P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1174
_refine_ls_wR_factor_ref         0.1187
_reflns_Friedel_coverage         0.000
_reflns_number_gt                5650
_reflns_number_total             6074
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5nj01642h2.cif
_cod_data_source_block           Ba4Ge2Sb2Se2Te8_C2
_cod_depositor_comments
'Adding full bibliography for 7063926--7063929.cif.'
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7063929
_shelx_shelxl_version_number     2019/1
_exptl_absorpt_special_details   SADABS-2016/2
_shelx_res_checksum              337