Metal–insulator transition in RNiO3 (R = Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er) induced by Li doping: A first-principles study.

Rare earth nickelates (RNOs) have been extensively studied in recent decades because of the metal–insulator phase transition, which can be driven by chemical doping. In the present study, we apply the first-principles calculation to investigate the electronic structures, optical properties, and migration behaviors of Li-doped RNO. Results show that when the doping ratio reaches 100%, RNO changes from the metallic state into an insulating state, which is confirmed by the experimental report. Regarding the optical properties, the absorption coefficient and reflectivity decrease in Li-doped RNO over the entire range of visible and infrared light compared with pristine systems. The migration of Li along the [001] direction of RNO is studied and shows that as the radius of rare earth atoms decreases, the migration barrier generally shows a gradually decreasing trend. These findings may shed light on the application of RNO in electrochromic devices. [ABSTRACT FROM AUTHOR]