Role of self-interaction effects in the geometry optimization of small metal clusters

¹ Departamento de Fisica da Universidade - 3000 Coimbra,  Portugal
² Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany

Received: 10 July 1995
Accepted: 8 February 1996

Abstract

By combining the Self-Interaction Correction (SIC) with pseudopotential perturbation theory, the role of self-interaction errors inherent to the Local Density Approximation (LDA) to Density-Functional Theory is estimated in the determination of ground-state and low-energy isomeric structures of small metallic clusters. Its application to neutral sodium clusters with 8 and 20 atoms shows that the SIC provides sizeable effects in , leading to a different ordering of the low-lying isomeric states compared with ab initio LDA predictions, whereas for the SIC effects are less pronounced, such that a quantitative agreement is achieved between the present method and ab initio LDA calculations.