Infrared spectra of HC2−∙(C2H2)n and O2−∙(C2H2)n clusters (n=2–5)

Abstract

We study the solvation of HC2- and O2- with acetylene ligands by means of midinfrared photodissociation spectroscopy in the CH stretching region, monitoring C2H2 evaporation upon infrared photon absorption by the parent cluster ions. Our findings are interpreted with the help of density functional theory. The infrared spectra indicate that while the binding generally occurs through ionic H bonds, there are two different classes of ligands which differ in their binding strength. This holds true for both core ions, even though their electronic structures and charge distributions are very different.