H Nb O3 Fourquet J, Renou M, de P, Theveneau H, Man P, Lucas O, Pannetier J Solid State Ionics 9 (1983) 1011-1013 H Nb O3, structure and NMR study _cod_database_code 1000189 _database_code_amcsd 0015505 7.645 7.645 7.645 90 90 90 Im3 atom x y z Nb1 .25 .25 .25 O1 0 .203 .303