Fe0.5 K3 O21 Ta7.5 Groult D, Chailleux J, Raveau B, Deschanvres A Revue de Chimie Minerale 14 (1977) 1-10 Nouveaux tantalates A3 (Ta8-x Mx) O21 a structure en cages _cod_database_code 1001299 _database_code_amcsd 0015378 9.12 9.12 12.086 90 90 120 P6_3/mcm atom x y z occ K1 .598 0 .25 Ta1 .248 0 .096 .9167 Fe1 .248 0 .096 .0833 Ta2 1/3 2/3 0 O1 .224 0 .25 O2 .792 0 .089 O3 .174 .497 .095