Mid/near infrared spectroscopy of the H2Cl+Ar cation complex compared to the predictions of anharmonic theory

Abstract

The H235Cl+Ar cation complex was prepared by electrical discharge in a supersonic expansion of argon doped with HCl and hydrogen. The ion was mass selected in a reflectron time-of-flight spectrometer and investigated with infrared photodissociation spectroscopy in the regions of 1000–4550 and 4850–7350 cm−1. Anharmonic vibrational frequencies were computed with VPT2 at the CCSD(T)/cc-pVTZ level of theory. The previously unreported ν3 fundamental at 2211 cm−1 and several new combinations and overtones are reported. VPT2 theory at this level confirms the H-bound structure of the complex and provides an accurate description of the anharmonic vibrations in this system.