F7 K2 Ta Hoard J Journal of the American Chemical Society 61 (1939) 1252-1259 Structures of complex fluorides. Potassium heptafluocolumbate. The Configuration of the heptafluocolumbate and heptafluortantalate ions _cod_database_code 1010050 _database_code_amcsd 0016986 5.85 12.67 8.5 90 90. 90 P2_1/c atom x y z Ta1 .266 .128 .223 K1 .236 .44 .188 K2 .757 .28 .445 F1 .045 .245 .2 F2 .455 .255 .205 F3 .045 .105 .4 F4 .455 .11 .41 F5 .225 -.025 .215 F6 .18 .11 .005 F7 .55 .075 .125