Localization of 3 d and 4 d electrons in small clusters : the roots of magnetism

Abstract

The photoelectron spectra of mass-selected negatively charged Nin- and Cun- clusters show similarities, which indicate an almost total localization of the Ni 3d orbitals corresponding to a maximum magnetic moment of 1μB per Ni atom. The similarity between Nin- and Cun- vanishes for n>7 corresponding to an increase in 3d delocalization. The data of Pdn- clusters suggest a Ni-like ( magnetic ) electronic structure for n = 3 6 and a Pt-like ( nonmagnetic ) one for n>15. There are indications that neutral Pd7 is a closed shell species (spin zero ground state).