METAL CLUSTER-RARE GAS VANDERWAALS COMPLEXES - NBNARM AND FENKRM

Van der Waals complexes of niobium clusters with argon atoms and iron clusters with krypton atoms have been produced in a supersonic expansion using a laser vaporization cluster source cooled to 77 K. Laser photoionization time-of-flight mass spectra reveal significant nonmonotonic cluster size dependence in the extent of formation for both NbnArm and FenKr species. Photoionization efficiency (PIE) spectra have been recorded for selected NbnArm species for n less-than-or-equal-to 20. For a given n, ionization potentials (IPs) assigned from PIE threshold behavior decrease with increasing m, as predicted by a simple charge-induced dipole electrostatic model.