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The effect of Ta substitution on the structural, microstructural, molecular and dielectric characteristics of Pb[Sc(sub)0.5Nb(sub)0.5]O(sub)3 (PSNT), synthesized by mechano-synthesis and conventional mixed oxide methods is studied. It is found that the ceramics show the formation of the materials in a single phase in the rhombohedral structure with the existence of nanodomain.

The influence of the lanthanum (La) substitution on structural, electrical and magnetic properties of bismuth ferrite ceramics in a wide range of temperature and frequency is investigated. The results reveal that the changes in the magnetic factors with La doping and the electron magnetic resonance parameters are measured at 300 K and 9.28 GHz with respect to increase in the magnetic anisotropy and magnetization.

The nanocrystalline Pb(sub 0.92)Nd(sub 0.08)(Zr(sub 0.53)Ti(sub 0.47))(sub 0.98)O(sub 3)(PNZT) is synthesized by high-energy ball milling (mechanical alloying). The analysis of impedance and dielectric properties of PNZT as a function of temperature has showed the high permittivity of 10626 at 10 kHz at the Curie temperature (Tc), broadening of permittivity peak, lowering of Tc, decrease in conductivity and increase in relaxation time with the decrease in crystalline size.

The metal-alkoxide sol-gel method was employed to prepare polycrystalline samples of Pb0.92(La1-zLi-z)0.08(Zr0.60Ti0.40)0.98+0.04zO3 (z=0.0, 0.1, 0.3, 0.5, 0.7) (PLLZT). Scanning electron microscopy and transmission electron microscopy were used to analyze respectively the formation of grain structure, particle size and distributions of the PLLZT materials. Further, systematic analyses were conducted on compositional dependence of ferroelectric behavior, dielectric loss, remanent polarization, coercive field, piezoelectric coefficients and pyroelectric coefficient of the materials. The results are discussed.

Polycrystalline samples of [Bi.sub.0.90][La.sub.0.10]([Fe.sub.1-x][Mn.sub.x])[O.sub.x] are prepared by using a mechanical activation followed by a conventional solid-state reaction method and their electric and magnetic properties at different Mn concentrations are examined. Grain and grain boundary conductivity has increased with a rise in temperature for all Mn concentrations and there is a systematic increase in the value of magnetization on increasing Mn concentration.

The ZnO thin films are prepared by using a cost-effective vacuum-carbon-arc technique combined with thermal oxidation under ambient conditions from zinc nanoparticles in carbon matrix. The downshift of phonon frequency and linewidth broadening of high frequency [E.sub.2] phonon mode are analyzed through defect state according to annealed conditions.

A study fabricated the polycrystalline nanosize (~60 nm) of (1-x)Pb(Fe2/3W1/3)O3-x(BiFeO3) solid solutions with a wide range of concentrations using a mechanical activation followed by a conventional solid-state reaction technique. Detailed dielectric studies of sintered pellets reveal that relaxor properties in Pb(Fe2/3W1/3)O3 (PFW) is induced with 10% addition of BiFeO3 (BFO) in (1-x)Pb(Fe2/3W1/3)O3+x(BiFeO3) (PBFW) solid solution.

A study fabricated the polycrystalline nanosize (~60 nm) of (1-x)Pb(Fe2/3W1/3)O3-x(BiFeO3) solid solutions with a wide range of concentrations using a mechanical activation followed by a conventional solid-state reaction technique. Detailed dielectric studies of sintered pellets reveal that relaxor properties in Pb(Fe2/3W1/3)O3 (PFW) is induced with 10% addition of BiFeO3 (BFO) in (1-x)Pb(Fe2/3W1/3)O3+x(BiFeO3) (PBFW) solid solution.

The electrical properties of ([Pb.sub.0.97][Sr.sub.0.03])([Zr.sub.0.05][Ti.sub.0.95]) (PSZT) are investigated by using a complex impedance spectroscopic technique in order to study the grain and grain boundary. The impedance spectroscopic analysis has showed the presence of both bulk and grain boundary effects in the material and the modulus analysis has indicated the possibility of hopping mechanism for electrical processes in the system with a nonexponential type of conductivity relaxation.

The effect of La substitution on the structural and electrical properties of multiferroic BiFeO3 thin films is reported which is grown on Pt/TiO2/SiO2/Si substrates by pulsed laser deposition. The reduction of dc leakage current of La-substituted films is examined on the basis of relative phase stability microstructure of the material.

The perovskite type structure of (Pb(sub 1-x)La(sub x)) (Zr(sub y)Ti(sub 1-y))(sub 1-x/4)O(sub3) (PLZT) ceramics is discussed. The complex impedance spectroscopy (CIS) technique is implemented on the (Pb(sub 1-x)La(sub x)) (Zr(sub y)Ti(sub 1-y))(sub 1-x/4)O(sub3) (PLZT) ferroelectric ceramics.

The nanocrystalline Gd-doped lead titanium zirconate (PGZT) with a high dielectric constant was synthesized by a combination of ball milling and sintering. The dielectric parameters of PGZT are decided significantly by the crystallite size according to the results obtained.