Structural phase transition of yttrium manganites on nickel substitution.

A series of nickel doped yttrium manganites having the representative formula Y1-xNixMnO3 with x = 0.0-0.1 in steps of 0.02 were prepared by conventional ceramic method. Analysis of the XRD pattern clearly showed the structural phase transformation from hexagonal to orthorhombic perovskite phase with nickel substitution. Variation of structural parameters such as lattice constant, crystallite size, theoretical density, etc. with nickel concentration was studied. Frequency variation of electrical properties such as dielectric constant, dielectric loss and ac conductivity were studied at room temperature in the range 3kHz-2MHz. The variation showed a dispersive behaviour for all the samples. [ABSTRACT FROM AUTHOR]