First-Principles Study on Structure and Stability of YAP Crystal

Abstract

The geometry optimization, formation energy, Mulliken populations, and density of states of YAP (YAlO3) crystal are studied by using first-principles method based on density functional theory. The optimal lattice parameters of YAP crystal are in good accordance with experimental results reported. The calculated formation energy (-3.73eV) indicates the excellent structural stability of YAP crystal. The obtained Mulliken charge populations of O, Al and Y atoms and their deviations from the formal ones, as well as overlap populations show YAP crystal is a mixed bond material with stronger ionic and weaker covalent bonds, which is attributed to the hybridization of atomic orbitals. The comprehensive effect of various interactions in the system makes YAP crystal more stable.