Structural, elastic, electronic, and optical properties of cubic perovskite CsCaCl3 are calculated using the full-potential linearized augmented plane wave method in the density functional theory. The exchange-correlation potential is evaluated using the local density approximation and generalized gradient approximation. Further, the modied BeckeJohnson potential is also applied for studying the electronic and optical properties. The calculated structural properties such as equilibrium lattice constant, the bulk modulus and its pressure derivative are in good agreement with the available data. The elastic properties such as elastic constants, anisotropy factor, shear modulus, Young's modulus and Poisson's ratio are calculated. The calculations of electronic band structure, density of states and charge density show that this compound has an indirect energy band gap (M Γ) with a mixed ionic and covalent bonding. Calculations of the optical spectra such as the real and imaginary parts of dielectric function, optical reectivity, absorption coecient, optical conductivity, refractive index, extinction coecient and electron energy loss are performed for the energy range of 030 eV. Most of the studied properties are reported for the rst time for CsCaCl3.

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Olivine-type LiNiPO 4 has been considered as a most competitive positive electrode active material for lithium-ion batteries. In the present paper, the LiNiPO 4 and Co-doped LiNi 0.5 Co 0.5 PO 4 are synthesized by solid-state reaction method under air atmosphere. All the X-ray diffraction peaks of both the compounds are indexed and it is found that the samples are well crystallized in orthorhombic olivine structure belonging to the space group Pnma. The crystallite size is calculated from the Scherrer formula and it is found to be 6.918 and 4.818 nm for pure and doped samples, respectively. The surface morphology and grain sizes of the materials are investigated through scanning electron microscope. Presence of preferred local cation environment is understood from Fourier transform infrared spectroscopy (FTIR) studies. The conductivity and dielectric analysis of the samples are carried out at different temperatures and frequencies using the complex impedance spectroscopy technique. The electrical conductivity of LiNi 0.5 Co 0.5 PO 4 is higher than that of pure LiNiPO 4 .