Ba Ni O5 Yb2 Garcia-Matres E, Rodriguez-Carvajal J, Martinez J, Alonso J, Salinas-Sanchez A, Saez-Puche R Solid State Ionics 63 (1993) 915-921 Polymorphism in the oxides R2NaNiO5 (R= Tm, Yb, Lu) _cod_database_code 1006062 _database_code_amcsd 0015516 12.1581 5.6423 6.9545 90 90 90 Pnma atom x y z Ba1 .9036 .25 .9244 Yb1 .2916 .25 .1241 Yb2 .0743 .25 .3998 Ni1 .6558 .25 .6952 O1 .4358 -.0040 .1701 O2 .2250 .4995 .3645 O3 .1035 .25 .0766