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Synthesis of mixed metal fluorides of the general formula, KMF 3 (M = Mg, Mn, Co, Ni, Cu and Zn), possessing perovskite structure was investigated in non-aqueous medium. The fluorides were characterized by powder X-ray diffraction, FT-IR spectroscopy, thermal analysis, SEM and TEM. Monophasic cubic phases were obtained for the central metal ions such as Mg, Mn, Co, Ni, and Zn and a tetragonally distorted phase was observed for Cu. The usage of non-aqueous medium is advantageous for the bulk synthesis of these fluorides, since it eliminated the generation and handling of the hazardous HF that has usually been encountered during aqueous preparations. The average crystallite size of the fluorides obtained by this approach was estimated to be in the range of 9-30 nm. SEM micrographs of KZnF 3 showed cubic morphology of perovskite phases. TEM studies on KCuF 3 confirmed the presence of tetragonal distortion. The fluoride content was determined by titrimetry and found to be nearly stoichiometric. Some of these fluorides were found to be thermally stable up to 225°C in air. These fluorides were employed as fluorinating agents in organic fluorination reactions, thereby suggesting their possible utilization for selective fluorination of aliphatic and aromatic hydrofluorocarbons (HFCs) that are industrially relevant.

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Compositions of (CaSrBa) orthosilicate phosphors were prepared by Liquid Phase Precursor method. The structural phase determinations were done systematically by powder X ray diffraction and Transmission electron microscopy. The PL emission was observed under 450 and 375 nm excitation and green red and pure green emission was observed for the 4f 6 5d ¼ 4f 7 transition of Eu 2+ ion. The luminescence nature of the samples is determined to vary with crystal field effect on the Eu 2+ ion and has been studied with the change in the binary Ca Sr, Ba Sr and ternary Ca Sr Ba compositions.