Electronic Structure of Lanthanum Hydrides with Switchable Optical Properties

摘要

Recent dramatic changes in the optical properties of LaH_{2+x} and YH_{2+x}films discovered by Huiberts et al. suggest their electronic structure isdescribed best by a local model. Electron correlation is important in H^--centers and in explaining the transparent insulating behavior of LaH_3. Themetal-insulator transition at $x\sim 0.8$ takes place in a band of highlylocalized states centered on the $H$-vacancies in the LaH_3 structure.