Structure and static response of small silver clusters to an external electric field

摘要

The static response properties and the structural stability of silverclusters in the size range $1\le n \le 23$ have been studied using a linearcombination of atomic Gaussian-type orbitals within the density functionaltheory in the finite field approach. The Kohn-Sham equations have been solvedin conjuction with a generalized gradient approximation (GGA)exchange-correlation functional. A proof that the finite basis set GGAcalculation holds the Hellmann-Feynman theorem is also included in theAppendix. The calculated polarizabilities of silver clusters are compared withthe experimental measurements and the jellium model in the spilloutapproximation. Despite the fact that the calculated polarizabilities are ingood agreement with both of them, we have found that the polarizability appearsto be strongly correlated to the cluster shape and the highest occupied-lowestunoccupied molecular-orbital gap.