Large, larger, largest ‒ a family of cluster-based tantalum copper aluminides with giant unit cells. I. Structure solution and refinement
Weber, Thomas; Dshemuchadse, Julia; Kobas, Miroslav; Conrad, Matthias; Harbrecht, Bernd; Steurer, Walter; Acta Crystallographica Section B 65 (2009) 308–317; doi:10.1107/S0108768109014001

data_2104373
_publ_section_title
;
 Large, larger, largest -- a family of cluster-based tantalum copper
 aluminides with giant unit cells. I. Structure solution and refinement
;
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              308
_journal_page_last               317
_journal_paper_doi               10.1107/S0108768109014001
_journal_volume                  65
_journal_year                    2009
_chemical_formula_sum            'Al282.23 Ta161.77'
_chemical_formula_weight         36886.85
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           216
_symmetry_cell_setting           cubic
_symmetry_space_group_name_Hall  'F -4 2 3'
_symmetry_space_group_name_H-M   'F -4 3 m'
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            1
_cell_length_a                   19.16630(10)
_cell_length_b                   19.16630(10)
_cell_length_c                   19.16630(10)
_cell_measurement_reflns_used    9013
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      66.6437
_cell_measurement_theta_min      4.2455
_cell_volume                     7040.68(6)
_computing_cell_refinement
;
CrysAlis RED, Oxford Diffraction Ltd.,
Version 1.171.32.24 (release 21-04-2008 CrysAlis171 .NET)
(compiled Apr 21 2008,18:23:10)
;
_computing_data_collection
;
CrysAlis CCD, Oxford Diffraction Ltd.,
Version 1.171.32.24 (release 21-04-2008 CrysAlis171 .NET)
(compiled Apr 21 2008,18:23:10)
;
_computing_data_reduction
;
CrysAlis RED, Oxford Diffraction Ltd.,
Version 1.171.32.24 (release 21-04-2008 CrysAlis171 .NET)
(compiled Apr 21 2008,18:23:10)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 8.1188
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.911
_diffrn_measurement_device_type  'Goniometer Xcalibur, detector: Onyx CCD'
_diffrn_measurement_method       \w-scan
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0560
_diffrn_reflns_av_sigmaI/netI    0.0537
_diffrn_reflns_limit_h_max       35
_diffrn_reflns_limit_h_min       -49
_diffrn_reflns_limit_k_max       30
_diffrn_reflns_limit_k_min       -46
_diffrn_reflns_limit_l_max       48
_diffrn_reflns_limit_l_min       -49
_diffrn_reflns_number            33911
_diffrn_reflns_theta_full        55.00
_diffrn_reflns_theta_max         67.28
_diffrn_reflns_theta_min         4.25
_exptl_absorpt_coefficient_mu    63.414
_exptl_absorpt_correction_T_max  0.3636
_exptl_absorpt_correction_T_min  0.1858
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlis RED, Oxford Diffraction Ltd.,
Version 1.171.32.24 (release 21-04-2008 CrysAlis171 .NET)
(compiled Apr 21 2008,18:23:10)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'metallic light grey'
_exptl_crystal_density_diffrn    8.700
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       irregular
_exptl_crystal_F_000             15478
_exptl_crystal_size_max          0.04
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.02
_refine_diff_density_max         9.802
_refine_diff_density_min         -10.346
_refine_ls_abs_structure_details
'Flack H D (1983), Acta Cryst. A39, 876-881, 2374 Friedel pairs'
_refine_ls_abs_structure_Flack   0.548(17)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.895
_refine_ls_matrix_type           full
_refine_ls_number_parameters     62
_refine_ls_number_reflns         5264
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.895
_refine_ls_R_factor_all          0.0602
_refine_ls_R_factor_gt           0.0383
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0426P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0807
_refine_ls_wR_factor_ref         0.0843
_reflns_number_gt                3661
_reflns_number_total             5264
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            sn5082.cif
_cod_data_source_block           at19
_cod_database_code               2104373
_cod_database_fobs_code          2104373