Density Functional Theory Investigations on the Structure and Electronic Properties of Normal Spinel ZnFe_2O_4

摘要

The structure and electronic properties of normal spinel ZnFe_2O_4 have been investigated using density functional theory (DFT) within the generalized-gradient approximation (GGA) and the local density approximation (LDA). The calculation results show that GGA/RPBE with ultrasoft pseudopotential method is a good method in predicting the crystal structures of the normal spinel ZnFe_2O_4. The results also indicate that the normal spinel ZnFe_2O_4 is direct gap semiconductor. There is a very strong hybridization between the Fe 3d state and the O 2p state, and a very strong hybridization between the Zn 3d state and O 2p state. The Zn—O bonds and Fe—O bonds have a covalent character.