Optical Spectra Description of the Insulator-Metal Transition of Nickel Monoxide by Volume Compression

Abstract

The electron energy loss spectra were used to determine the insulator-metal transition point of nickel monoxide by volume compression. The optical spectra are based on electronic structures which have been obtained using the density functional theory implemented in the MindLab 5 code that employed the local density approximation plus the Hubbard on-site Coulomb interaction parameter (LDA+U) functional. At increasing volume compression, we observed a sharp rise in the electron energy loss spectrum at 0.60 volume compression ratio indicating inter-band transition.