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We have grown a single crystal of Ascorbic acid (a drug) containing Potassium nitrate as an additive by aqueous solution method. Good semi transparent, semi organic nonlinear optical crystals were obtained in a period of 3 weeks. The cell parameters of the grown crystals were estimated by single crystal X-ray diffraction analysis. The X-ray powder diffraction further confirms the crystalline properties of the grown crystals. Thermal analysis was performed to study the thermal stability of the grown crystals. The presence of functional groups and mode of vibrations were identified from the FTIR spectrum. The powder second harmonic generation (SHG) of the grown crystal was measured by Kurtz technique using Nd: YAG laser. Scanning Electron Microscopic (SEM) studies reveals the morphology of the crystals.

This paper deals with the preparation of Zirconium Nitride films by DC reactive magnetron sputtering. Films were deposited on silicon substrates at room temperature. Nitrogen partial pressure was varied from 4 × 10⁻⁵ to 10 × 10⁻⁵ m bar and the effect on the structural, electrical, optical properties of the films was systematically studied. The films formed at a nitrogen pressure of 6 × 10⁻⁵ mbar showed low electrical resistivity of 1.726 × 10⁻³ Ω.cm. The deposited films were found to be crystalline with refractive index and extinction coefficient 1.95 and 0.4352 respectively. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Abstract: Undoped KDP and KDP crystals containing KI/NaI with/without gold doping were grown by slow evaporation technique. All the grown crystals were γ-irradiated using60Co source. Electrical conductivity measurements were carried out on all these crystals perpendicular to the unique direction before and after y-irradiation. The present results show that the conductivity of KDP crystals increases with the addition of KI/NaI and with gold doping as well as upon rise in temperature. Computed values of activation energies from the conductivity measurements are given. For all the grown crystals, dielectric constant is measured as a function of frequency.

Chlorine n.q.r, in 2,6-dichlorophenol has been investigated at temperatures from 77 K to room temperature. Two resonance lines due to chemically inequivalent sites have been observed throughout this temperature range. Torsional frequencies of the molecule have been calculated at temperatures from 77 to 300 K according to Bayer's theory and Brown's method. Also the temperature coefficients of the torsional frequencies have been calculated.

The torsional frequencies have been rigorously evalulated in the compounds 1,2,4,5-tetrachloro-3,6-dinitrobenzene and 1,3,5-trichloro-2,4-dinitrobenzene over an extended temperature range (77K–392K) using the experimental results of NQR and crystal structure data. The values have been compared with those obtained by using the X-ray thermal parameters.

N.q.r. in sodium chloroacetate has been investigated at temperatures from 77 K to room temperature (c.300 K). A single line has been observed throughout this temperature range. Torsional frequencies of the molecule have been calculated in the above temperature range from Bayer's theory. Also the temperature coefficient of the torsional frequencies has been calculated by Brown's method.