研究目的

To study and compare the ground state structural parameters, electronic behaviour and optical properties of the cubic and orthorhombic BaThO3.

研究成果

The results of the electronic structure and optical properties of BaThO3 in cubic and orthorhombic phases using the FP-LAPW method and employing the LDA, GGA and mBJ approximations are in good agreement with the experimentally measured value and the analytical reported works. A small difference has been noticed between the LDA and GGA approximation in the most parts of the properties study. The difference is more noticeable in the lattice constants and volume calculated and in the density of states. Further, we have used the mBJ-functional which gives larger gaps close to the experimental values (Eg=5.61eV) so that the optical transitions are located correctly visible in the imaginary part of the dielectric function. The direct and wide band gap confirms that these materials are useful for optoelectronic devices in the UV region spectrum.

研究不足

DFT usually underestimate physical quantities. In the present work the calculated lattice constant for the cubic BaThO3 is in good agreement with the experimentally measured value and the analytical reported works. Similarly, for orthorhombic phase the lattice constant is in good agreement with the analytical and experimental work.