Electronic, chemicM bonding and optical properties of cubic Hf3N4 ( c-Hf3N4 ) are calculated using the first- principles based on the density functional theory (DFT). The optimized lattice parameter is in good agr...Electronic, chemicM bonding and optical properties of cubic Hf3N4 ( c-Hf3N4 ) are calculated using the first- principles based on the density functional theory (DFT). The optimized lattice parameter is in good agreement with the available experimental and cedculational values. Band structure shows that c-Hf3N4 has direct band gap. Densities of states (DOS) and charge densities indicate that the bonding between Hf and N is ionic. The optical properties including complex dielectric function, refractive index, extinction coefficient, absorption coefficient, and refleetivity are predicted. Prom the theory of crystal-field and molecular-orbited bonding, the optical transitions of c-Hf3N4 affected by the electronic structure and molecular orbited are studied. It is found that the absorptive transitions of c-Hf3N4 compound are predominantly composed of the transitions from N T2 2p valence bands to Hf T2 (dxy, dxz, dyz) conduction bands.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No. 50902110the Natural Science Foundation of Shaanxi Province under Grant No. 2012JM6012+2 种基金the Research Fund of the State Key Laboratory of Solidification Processing under Grant No. 58TZ-2011the 111 Project under Grant No. B07040the Northwestern Polytechnical University Foundation for Fundamental Research under Grant No. JC20110245
文摘Electronic, chemicM bonding and optical properties of cubic Hf3N4 ( c-Hf3N4 ) are calculated using the first- principles based on the density functional theory (DFT). The optimized lattice parameter is in good agreement with the available experimental and cedculational values. Band structure shows that c-Hf3N4 has direct band gap. Densities of states (DOS) and charge densities indicate that the bonding between Hf and N is ionic. The optical properties including complex dielectric function, refractive index, extinction coefficient, absorption coefficient, and refleetivity are predicted. Prom the theory of crystal-field and molecular-orbited bonding, the optical transitions of c-Hf3N4 affected by the electronic structure and molecular orbited are studied. It is found that the absorptive transitions of c-Hf3N4 compound are predominantly composed of the transitions from N T2 2p valence bands to Hf T2 (dxy, dxz, dyz) conduction bands.