Ba Ca0.34 Er1.66 Ni O4.58 Alonso J, Rasines I, Rodriguez-Carvajal J, Torrance J Journal of Solid State Chemistry 109 (1994) 231-240 Hole and electron doping of R2BaNiO5 (R=rare earths) _cod_database_code 1006071 _database_code_amcsd 0013806 3.6876 5.7467 11.3012 90 90 90 Immm atom x y z occ Ca1 .5 0 .2049 .17 Er1 .5 0 .2049 .83 Ba1 .5 .5 0 Ni1 0 0 0 O1 0 .2405 .1476 .99 O2 .5 0 0 .62