Novel Refractory Phase, Ta7Si2(SixB1-x)2
V. Romaka; V. Fosodeder; P. F. Rogl; É. C. T. Ramos; C. A. Nunes; G. C. Coelho; G. Giester; Inorganic Chemistry 52 (2013) 11295–11301; doi:10.1021/ic401413f

data_4336193
_publ_section_title
;
 Novel Refractory Phase, Ta7Si2(SixB1-x)2
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              11295
_journal_page_last               11301
_journal_paper_doi               10.1021/ic401413f
_journal_volume                  52
_journal_year                    2013
_chemical_formula_sum            'B0.88 Si1.12 Ta3.5'
_chemical_formula_weight         674.30
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           127
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  '-P 4 2ab'
_symmetry_space_group_name_H-M   'P 4/m b m'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_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            4
_cell_length_a                   6.222(2)
_cell_length_b                   6.222(2)
_cell_length_c                   8.328(2)
_cell_measurement_temperature    298(2)
_cell_volume                     322.40(17)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.975
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0234
_diffrn_reflns_av_sigmaI/netI    0.0191
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            1357
_diffrn_reflns_theta_full        35.98
_diffrn_reflns_theta_max         35.98
_diffrn_reflns_theta_min         4.63
_exptl_absorpt_coefficient_mu    118.550
_exptl_crystal_density_diffrn    13.892
_exptl_crystal_F_000             1102
_refine_diff_density_max         3.497
_refine_diff_density_min         -3.657
_refine_diff_density_rms         0.739
_refine_ls_extinction_coef       0.00128(11)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.308
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     19
_refine_ls_number_reflns         437
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.308
_refine_ls_R_factor_all          0.0263
_refine_ls_R_factor_gt           0.0237
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0121P)^2^+11.3223P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0478
_refine_ls_wR_factor_ref         0.0485
_reflns_number_gt                422
_reflns_number_total             437
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic401413f_si_001.cif
_cod_data_source_block           tabsi
_cod_original_cell_volume        322.41(17)
_cod_original_formula_sum        'B0.88 Si1.12 Ta3.50'
_cod_database_code               4336193