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Composites of BaTiO3 and CoFe204 have been prepared with various compositions by double sintering method. The presence of the two phases has been confirmed by XRD. Variation of dielectric constant with temperature in these samples has beeaa studied. All the samples have shown linear magnetoelectric conversion in the presence of static magnetic field. The magnetoelectric effect (dE/dH) has been studied as a function of intensity of magnetic field. The maximum value of the conversion factor (dH/dH)mjx was found to be 0"16 mV/cra/Oe.

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The compound, LaBi 5 Fe 2 Ti 3 O 18 , is a five-layered material belonging to the family of bismuth layered structure ferroelectromagnetics. D.c. and a.c. conductivity measurements were performed on the samples. Dielectric measurements were also performed on these samples. Combined impedance and modulus plots were used as tools to analyse the sample behaviour as a function of frequency. Cole-Cole plots showed non-Debye relaxation.

The magnetoelectric property of composite materials consisting of piezoelectric and piezomagnetic constituents are of interest since the stresses induced in them on application of an external magnetic field are converted into electrical signals. The electrical output is primarily due to electromagnetic coupling between the two participating phases. The present paper deals with the evaluation of the electromechanical coupling in the magnetoelectric composite consisting of 50% lead zirconate titanate (Pb0.96Sr0.04Ti0.47Zr0.53O3) and 50% CoFe2O4, the composition having maximum magnetoelectric conversion efficiency. A sum rule is proposed to calculate the electromechanical coupling coefficient and the results are correlated with the experimental data.

An experimental setup is devdoped for the measurement of dynamic magnetoelectric effect (ME) in polycrystalline materials, using a time varying DC magnetic field on which an AC magnetic fidd is superimposed. The experimental data on ME on BisFeTi3015 and a solid solution of (90%)BiFeO3-(10%)BaTiO 3 are obtained using this setup. The linear and higher order ME coefficients can be evaluated from the output voltage. The temperature variation of ME data gives additional information corroborating with the data on magnetization.

CoxCdl_xC2044H20 crystals grown by gel technique are characterized for dielectric properties by optical absorption measurements. Loss curve shows a relaxation peak at 500 KHz corresponding to a relaxation time of 0"3 #s. Cole-Cole diagrams give exponent of universal power law to be equal to 0'22. Optical absorption shows peaks due to Co ÷ 2 ion and water of hydration. An attempt is made to understand the results.