Structure and Cohesive Energy of Cu Clusters（Ⅲ）——Average Atomic-distance Contraction

Based on the Embedded-Atom Method, we have performed a semiempirical calculation of structure for f_cc cuboctahedra copper clusters with number of atoms from 13 to 201. The corresponding average atomic-distance contractions have been derived. It is found that the distances between inner atoms are approximately equal to that or bulk metal and do not change with cluster size, while the surface atoms clearly contract along longitudinal direction, which result in the atomic-distance contraction effect. The average atomic-distance contraction is roughly inversely propotional to clusterdiameter. Our calculated results have been compared with available experimental data.