Strong metal-cage hybridization in endohedral La@C-82, Y@C-82 and Sc@C-82

Stimulated by the recent resonant photoelectron spectroscopy studies on La@ C-82 who found a nonzero charge density localized on the La atom, local den sity functional calculations have been performed on La@C-82, Y@C-82 and Sc@ C-82. In contrast to previous charge transfer model for La@C-82, Y@C-82 and d-electron localization model for Sc@C-82, strong hybridization between th e La (Y, Sc) d valence orbitals and the cage orbitals have been found in ou r calculations. Through hybridization the unpaired electron is primarily de localized on the cage but the occupied valence orbitals contain significant d character. (C) 2000 Elsevier Science B.V. All rights reserved.