Structural and physical properties of the solid solution series Bi4V2-xNixO11-1.5x

The compounds Bi4V2-xNixO11-1.5x, x less than or equal to 0.35, were prepar ed by solid state reaction. The alpha phase is present at room temperature for x less than or equal to 0.20 and the gamma phase is stable for greater Ni concentrations, The oxygen ion vacancies in the x = 0.30 phase exist in the equatorial plane of the V/Ni coordination octahedron. The x = 0.30 phas e is paramagnetic, As the Ni concentration decreases the magnetic spin stru cture gradually changes to that of an amorphous spin glass. At 833 K the io nic conductivity sigma = 3.16 x 10(-2) S cm(-1). The ionic conductivity dec reases with increasing Ni concentration. (C) 1999 Academic Press.