A New Monoclinic Phase of Cerium Orthovanadate (CeVO4)

摘要: A new monoclinic phase of cerium orthovanadate, CeVO4(H), was found during the course oxidation pseudo-perovskite CeVO3 below 400°C. It has been confirmed to crystallize in huttonite-type structure (C2h5−P21⁄n), that LaVO4. The lattice parameters were determined be:a0=6.98A, b0=7.22A, c0=6.76A, β=105°02′, V=328A3 and Z=4.This metastable, exothermally transformed into a known stable CeVO4 (tetragonal zircon-type, D4h19−I41⁄amd) above 400°C, releasing small amount oxygen. From magnetic, chemical thermogravimetric analyses, valences ion vanadium CeVO4-(H) seem be tripositive pentapositive respectively, but V4+ is mixed zircon-type CeVO4; CeVO4(Z).