A NEW BOUNDARY TREATMENT - HF SURFACE-POTENTIAL MODEL APPLIED TO SOLID-STATE CLUSTER CALCULATIONS

A new boundary treatment, a Hartree-Fock (HF) surface potential model, is proposed to deal with the surface effect in the solid-state cluste r calculations using the LCAO-MO-SCF ab initio method. The surface pot ential arises from one or more atoms, which have no basis function and are added to the calculated cluster system. These atoms are placed in such sites so that the HF potential field of the calculated system sh ould possess a point-group symmetry. The surface potential could be fo und by the corresponding HF potential using a symmetry operator. The f act that a rather symmetric electronic structure of the asymmetric clu ster YBa2CuZn2O7 is obtained using the HF surface potential shows that the surface effect in the cluster calculations could be neutralized t o a great extent. (C) 1995 John Wiley & Sons, Inc.