Analysis of the Mn–O and Y–O bonds in paraelectric and ferroelectric phase of magnetoelectric YMnO3 from the first principles calculations

摘要: Abstract We report the first-principles band-structure calculations on multiferroic hexagonal YMnO3, realized with objective to study how Mn–O and Y–O bonds change when compound undergoes paraelectric (PE) ↔ ferroelectric (FE) phase transition. The was simulated in non-magnetic antiferromagnetic configuration. Exchange–correlation effects were treated by modified Becke-Johnson approach, which enabled successful reproduction of experimental band gap FE predicted a small PE phase, agreement findings. investigated qualitatively, inspecting charge density maps projected onto suitable planes, quantitatively, applying Bader's topological analysis comparing electronic densities states different phases. Independently fact Mn ions treated, as spin-polarized or not, results indicate that do not suffer significant changes during PE-FE transition, while become more covalent, clear signs hybridization between Y 4 d z 2 O pz orbitals. from present study, therefore, substantiate d0-ness model explain ferroelectric distortion manganites.