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New rare earth vanadates YSr_(Q-x)Ca_xV_3O_(9-y)(x=0.0, 0.67, 1.0, 1.33 and 2.0) have beensynthesized by a new simple method. X-ray powder diffraction results show that they are mono-phase.They belong to orthorhombic structure and their lattice constants are calculated. The results ofweight gains in TG curves show that the lower valent vanadium is oxidized to higher valent state athigher temperature. The oxygen contents of new compounds are calculated from the weight gains.Both V~(3+) and V~(4+) coexist in YSr_(2-x)Ca_xV_3O_(9-y). These compounds exhibit low electric resistivity atroom temperature.
New rare earth vanadates YSr_ (Qx) Ca_xV_3O_ (9-y) (x = 0.0, 0.67, 1.0, 1.33 and 2.0) have been designed by a new simple method. X-ray powder diffraction results show that they are mono- belong to orthorhombic structure and their lattice constants are calculated. The results ofweight gains in TG curves show that the lower valent vanadium is oxidized to higher valent state athigher temperature. The oxygen contents of new compounds are calculated from the weight gains.Both V ~ ( 3+) and V ~ (4+) coexist in YSr_ (2-x) Ca_xV_3O_ (9-y). These compounds exhibit low electric resistivity atroom temperature.