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.

中文翻译：

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Li掺杂诱导的RNiO3(R=Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er)中的金属-绝缘体跃迁：第一性原理研究

近几十年来，由于金属-绝缘体相变，稀土镍酸盐 ( R NOs) 得到了广泛的研究，这可以由化学掺杂驱动。在本研究中，我们应用第一性原理计算来研究 Li 掺杂R NO的电子结构、光学性质和迁移行为。结果表明，当掺杂比例达到 100% 时，R NO 从金属态转变为绝缘态，实验报告证实了这一点。关于光学特性，与原始系统相比，在整个可见光和红外光范围内，掺杂锂的R NO的吸收系数和反射率降低。Li沿[001]方向迁移R NO 的研究表明，随着稀土原子半径的减小，迁移势垒一般呈逐渐减小的趋势。这些发现可能有助于阐明R NO 在电致变色器件中的应用。