Varghese Mathew

Spectroscopic studies of gel-grown lanthanum malonate crystals

Lanthanum malonate crystals were grown by single tube ionic diffusion through silica gel.The crystallinity of the grown crystals was analyzed by powder X-ray diffraction studies.Fourier transform infrared spectroscopy (FTIR) and fourier transform (FT) Raman studies confirmed the presence of functional groups in the title compound.The optical band gap energy of the material was extracted ftom diffuse reflectance spectrum.

SPECTROSCOPIC AND THERMAL STUDIES OF GEL-GROWN COPPER MALONATE CRYSTALS

Copper malonate crystals were grown using silica gel as the growth medium. The grown crystals were characterized by X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR) and Fourier transform Raman spectroscopy (FT Raman). The thermal decomposition of the compound was investigated using thermogravimetry (TG) and derivative thermogravimetry (DTG) measurements.

Thermal and dielectric properties of gel-grown cobalt malonate dihydrate single crystals

Single crystals of cobalt malonate dihydrate were grown in a silica gel medium by the single diffusion method. The thermal behavior of the crystals was investigated by thermogravimetric and differential thermal analyses. The dielectric constant, dielectric loss and ac conductivity of the crystals were estimated as a function of temperature in the range 40–140 °C for four different frequencies. The results indicate that the grown crystals are thermally stable up to about 150 °C and exhibit a phase transition at 130 °C.