AgInSe 2 crystals were grown by Bridgman technique. The crystals were identified structurally by X-ray diffraction technique. Measurements of electrical conductivity and Hall effect were performed in the temperature range (138 K-434 K) and (220 K-488 K) for thermoelectric power measurements. From these measurements, many physical parameters were determined. The energy gap was calculated to be 1.24 eV. The conductivity type was found to be n-type. Crystallite size (D) of the obtained AgInSe 2 crystals was calculated to be 70 nm. The lattice parameters for the prepared crystals were a = 6.0938 Å and c = 11.7775 Å.

By means of permittivity, spontaneous polarisation and polarisation reversal measurements the authors studied the influence of the substitution of deuterium atoms for hydrogen on the ferroelectric properties of tris-sarcosine calcium chloride (TSCC). Although most of the protons in the hydrogen bonds were substituted by deuterium (as checked by means of multi-pulse NMR techniques for solids and by infrared spectroscopic measurements) there is no change of the phase transition temperature. By combining density and NMR measurements it could also be shown that the volume of the unit cell did not alter for the various deuterated crystals. The absence of the deuteration effect on Tc and on the parameters of the Landau expansion of Ps suggests that a proton ordering in the hydrogen bond of the type N-H. . .Cl does not occur in practice. This behavior can be understood because the hydrogen bond is rather asymmetric so that the protons occupy predominantly equilibrium positions near the nitrogen atoms. For an interpretation of the results presented the theory of Chaudhury (1982) and co-workers may be applied.

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Lead lanthanum titanate, (PLT) ceramics were fabricated by conventional combustion technique andthe influence of different sintering temperature (1170, 1200, 1230, 1260 and 1300 o C) at a fixed of sintering time for 2h on the microstructure and dielectric properties were investigated. The particle size of PLT ceramics which can be calculated by Scherer formula from XRD (x-ray diffraction)

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