New Insight into Mechanical Stability, Electronic and Elastic Properties of Paraelectric h-YMnO3 from First-Principles Calculations

Abstract

In this work, we represent for the first time a study on h-YMnO3 oxide in the para-electric phase using ab initio calculations, including equation of state, mechanical stability, electronic, magnetic and elastic properties. This theoretical study has been conducted using the full potential-linearized augmented plane wave method (FP-LAPW) within the framework of density functional theory (DFT). We also used the Tran-Blaha modified Becke-Johnson (TB-mBJ) for band structure calculations, as implemented in the wien2k code. Our calculations including internal atomic relaxations are in very good agreement with the available experimental data. Spin-polarized electronic band structure exhibits semiconductor behavior with a low band gap observed equal to 0.4 eV. The calculated elastic constants Cij confirm the mechanical stability of our oxide. The estimated anisotropy factors show that h-YMnO3 has a strong anisotropic character. To our knowledge, this is the first theoretical study on h-YMnO3 oxide in paraelectric phase, which still awaits experimental confirmations.