First-principles calculations to study the metal-insulator transition of Al and Be doped RNiO3 (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho and Er)

Rare earth nickelates (RNO) have been extensively studied in the past decades because of the metal-insulator phase transition. It was reported that the phase transition of RNO could be regulated with the electrons introduced by Li and H doping, but little is known about the multi-electrons (such as Be, Al) doping of RNO. In this paper, we applied the first-principles calculations to investigate the electronic structures, interstitial formation energies, migration behaviors and optical properties of Be and Al doped RNO. Results show that RNO would undergo a metal-insulator phase transition when the Be and Al doping concentrations respectively reach 50% and 25%. In addition, the migration of Be and Al along the [001] direction of RNO shows that as the radius of rare earth atoms decreases, the migration barrier generally shows a decreasing trend. As for optical properties, the absorption coefficient and reflectivity decrease in Be and Al doped RNO over the entire range of visible and infrared light. Generally, the transmissivity of RNO can be greatly improved by doping 50% of Be and Al.