Investigation of vibrational properties and ferroelectric instability of doped perovskite barium titanate (BaTi0.6Nb0.2Fe 0.1O3)

Abstract

The structural and vibrational properties of doped and non-doped tetragonal barium titanate were predicted from density functional theories (DFT) with LDA and GGA/PW91. The doped structures were doped with niobium ion (Nb5+) and ferrous (Fe2+) that substitute at the titanium sites. All possible structures were generated and assessed. The results indicate that the splitting of phonon modes was observed in doped structures which have been considered responsible for the ferroelectric instability. © 2014 Copyright Taylor and Francis Group, LLC.