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The Zn(4s 2 )·Ne[ 1 Σ + ] and the Zn(4s4pπ)·Ne[ 1 Π 1 ] states have been characterized by laser-induced fluorescence spectroscopy. Bond lengths were determined from simulations of the partially-resolved rotational structure of the 1 Π ← 1 Σ + transitions, while bond strengths were estimated from a Birge–Sponer extrapolation with allowance for consistent errors resulting from similar procedures in the analogous Cd·Ne and Hg·Ne transitions. The van der Waals bonding in these states is discussed briefly and compared to that in the analogous M·RG states, where M=Mg, Zn, Cd, Hg and RG=Ne, Ar, Kr, Xe.

The luminescence spectroscopy of atomic zinc isolated in the solid rare gases (ZnRG) is compared with theoretical predictions obtained with the use of diatomic Zn·RG potentials. In particular, the existence of pairs of emission bands, both of which are assigned to the same gas-phase electronic transition, is examined with the use of diatomic pair potentials to simulate the potential-energy surfaces of the Jahn-Teller active vibrational modes of Zn in the solid. The close agreement found between theory and experiment indicates the validity of the use of pair potentials in the analysis of matrix zinc spectroscopy. Thus, it allows identification of the high-energy emission bands in the ZnRG systems as arising from motions of the rare-gas atoms surrounding the atomic zinc guest and the lower-energy bands as associated with the motion of the zinc atom into an octahedral interstitial site in the lattice.

We have observed the time dependence of the motion of the atoms in a van der Waals complex (HgAr). This motion leads to direct dissociation or corresponds to vibrations in the potential well. The time evolution is similar to that observed in the femto-second domain for chemically bound molecules, i.e. it leads to appearance of transients and vibrational recurrences. In softening the potentials, the characteristic time for the movements of the atoms is slowed down to the picosecond. We have observed and analyzed the direct dissociation and the vibrational recurrences in the B potential well.

Structured progressions, assocd. with the Cl-Rg+ and H-Rg+ charge transfer species, are obsd. for Cl and H atoms isolated in Kr and Xe (Rg) crystals and are assigned as transitions to Rydberg states. The Rydberg levels correspond to delocalized pos. hole states in the rare gas solid (Rg+) orbiting a neg. center (Cl- or H-). For OH in Ar and Kr matrixes, transitions to static charge transfer states are identified. For both of these rather extreme situations, simple model are used successfully to predict the transition energies. For the former, an exciton model based on the effective mass approxn. and utilizing quantum defect nos. is used, while in the latter, a Coulombic potential screened by the medium is used. [on SciFinder (R)]