The properties of neutral and anionic ${\mathrm{Pd}}_N$ clusters were investigated with spin-density-functional calculations. The ground-state structures are three dimensional for $N>\mathrm{}3\mathrm{}$ and they are magnetic with a spin triplet for $2\le N\le 7$ and a spin nonet for $N=13\mathrm{}$ neutral clusters. Structural and spin isomers were determined and an anomalous increase of the magnetic moment with temperature is predicted for a ${\mathrm{Pd}}_7$ ensemble. Vertical electron detachment and ionization energies were calculated and the former agrees well with measured values for ${\mathrm{Pd}}_N^{-}$.

• Received 15 August 2000

DOI:https://doi.org/10.1103/PhysRevLett.86.2545