data_global _amcsd_formula_title 'F7 K2 Ta' loop_ _publ_author_name 'Hoard J' _journal_name_full 'Journal of the American Chemical Society' _journal_volume 61 _journal_year 1939 _journal_page_first 1252 _journal_page_last 1259 _publ_section_title ; Structures of complex fluorides. Potassium heptafluocolumbate. The Configuration of the heptafluocolumbate and heptafluortantalate ions _cod_database_code 1010050 ; _database_code_amcsd 0016986 _chemical_formula_sum 'Ta K2 F7' _cell_length_a 5.85 _cell_length_b 12.67 _cell_length_c 8.5 _cell_angle_alpha 90 _cell_angle_beta 90. _cell_angle_gamma 90 _cell_volume 630.016 _exptl_crystal_density_diffrn 4.134 _symmetry_space_group_name_H-M 'P 1 21/c 1' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,1/2-y,1/2+z' '-x,1/2+y,1/2-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z Ta1 0.26600 0.12800 0.22300 K1 0.23600 0.44000 0.18800 K2 0.75700 0.28000 0.44500 F1 0.04500 0.24500 0.20000 F2 0.45500 0.25500 0.20500 F3 0.04500 0.10500 0.40000 F4 0.45500 0.11000 0.41000 F5 0.22500 -0.02500 0.21500 F6 0.18000 0.11000 0.00500 F7 0.55000 0.07500 0.12500