Crystal structure of perovskite type CeGaO₃ synthesized by arc- and skull- melting methods

Crystalline phase of CeGaO₃ has been successfully synthesized by two kinds of methods; arc- and skull- melting methods. In the case of arc -melting method, CeGaO₃ is finally obtained by a reaction of Ce₂O₃ and Ga₂O₃, where, Ce₂O₃ is produced by a "thermal effect on the reduction" from the source CeO₂ in the first reaction stage. On the other hand, in the case of skull-melting method, CeGaO₃ is obtained by a "direct reduction" of Ga₂O₃ by Ce. Both crystallographic data on CeGaO₃ obtained by two methods are consistent. The structure belongs to tetragonal system with space group, P4/mmm, which is different from cubic system as reported in literatures. Lattice constants are a=0.3873(1)nm, c=0.3880(1)nm, V=0.5819(3) × 10^-28 m³, Z=1. This compound is unstable at high temperature in air and decomposes to CeO₂ and Ga₂O₃ by heating up to 1250 °C.