Theoretical and Experimental Studies on the Crystal Structure, Electronic Structure and Optical Properties of SmTaO4

Abstract

The crystal structure, electronic structure and optical properties of SmTaO4 were identified through an experimental method and first principles calculation. X-ray powder diffraction (XRD) and a spectrophotometer were used to characterize the crystal structure, reflectivity and band gap of this material; furthermore, the electronic structure and optical properties were investigated according to three exchange-correlation potentials, LDA, GGA and GGA + U. Results show that the SmTaO4 calcined at 1400 °C with the solid-state reaction method is in monoclinic phase in the space group I2/a. In addition, the calculated lattice parameters are consistent with the experimental values. The electron transitions among the O 2p states, Sm 4f states and Ta 5d states play a key role in the dielectric function, refractive index, absorption coefficient and reflectivity of SmTaO4. The calculation of first principles provides considerable insight into the relationship between the electronic structure and optical properties of this material.

Hydrothermal synthesis and characterization of novel yellow pigments based on V5+ doped BiPO4 with high near-infrared reflectance

“…To be more specic, the energy coordinates of the dot on the low-energy side of the plot where the linear increase in the function ([F(R)hn] 2 ) starts have been deemed to be the value of the band gap energy of the semiconductors. 37 As shown in Fig. 7, the band gap of the pigments varies over the range from 3.657 to 3.244 eV as the incorporation of V 5+ increases, so the color of the samples changes from white to yellow.…”

Phase Composition of Samarium Niobate and Tantalate Thin Films Prepared by Sol-Gel Method

“…SmNbO 4 ceramics were annealed at 1200-1300°C with monoclinic and tetragonal structure [5,6]. Polycrystalline SmTaO 4 were heating at 1400°C with single monoclinic M and M´-type structure [7,8], respectively.…”