Infrared investigations of negatively charged complexes and clusters

Abstract

The review describes recent progress in the characterization of size-selected negatively charged clusters in the gas phase using vibrational predissociation spectroscopy. Examples from the authors' laboratory are used to demonstrate the way in which spectra are obtained and interpreted to provide information on anion-neutral interactions. Infrared studies of simple dimer complexes consisting of hydrogen molecules attached to halide anions (Cl--H2, Br--H2, I--H2) are described. From rotationally resolved spectra in the 2.5 μm H-H stretch region one can deduce that the complexes have linear equilibrium structures and can ascertain intermolecular separations. Corresponding spectra of the Cl--D2..