Intermolecular potential between an atom and a linear molecule: The structure of ArOCS

Abstract

The radio frequency and microwave spectrum of ArOCS has been measured by molecular beam electric resonance spectroscopy. ArOCS is a prolate, slightly asymmetric top. The rotational constants and dipole moment components of the ground vibrational state are as follows: A = 6786.014(20) MHz, B = 1509.909(6) MHz, C = 1227.220(6) MHz, μa = 0.2146(10) D, μb = 0.669(2) D. The complex has a nonlinear, T-shaped structure and the vibrationally averaged distances are Ar–C = 3.578(1), Ar–O = 3.601(1), and Ar–S = 4.101 Å. The observed structure is analogous to isoelectronic and isovalent chemically bound systems, and it is shown to be that expected from an interaction of the highest occupied orbital of Ar with the lowest unoccupied orbital of OCS.