Electron Spectroscopy and the Electronic Structure of KNbO₃: First Principle Calculations

Abstract

The electronic structures of KNbO₃were calculated within the density functional theory, and their evolution was analyzed as the crystal-field symmetry changes from cubic to rhombohedral via tetragonal phase. We carried out electron-energy loss spectroscopy experiments by using synchrotron radiation and compared the results with the theoretical spectra calculated within Density Functional Theory. The dominant role of the NbO₆octahedra in the formation of the energy spectra of KNbO₃compound was demonstrated. The anomalous behavior of plasmons in ferroelectrics was exhibited by the function representing the characteristic energy loss in the region of phase transition.

Keywords:

• KNbO₃
• electron energy loss
• plasmon