An Extended Huckel Study of Ce/Si(111) Chemisorption
Ce在Si(111)面上吸附的EHT研究方法

Semiempirical EHT method is used in studying the chemisorption of rare earth Ce on Sl(111).Cluster models are used to simulate two possible sites-the top site and the threefold site.The latter is found to be more stable than the former.The optimized vertical dis-tance between Ce and the surface is obtained as 4.0 a.u. on the three-fold hollow site, whichagrees very well with the result of the first principle DVM calculation.The energy shift ofvalence levels and the charge transfer are alsc in good agreement with the results of DVM.This provides a simple and flexible method to study the problem.