Vacuum Ultraviolet Laser / Time-of-flight Spectroscopy of Cl2.

Abstract

Vacuum ultraviolet (VUV) spectra of Cl2 are highly irregular due to extensive excited state perturbations, and in the past, have been difficult to interpret1. This situation was offset substantially by the ab initio calculations of Peyerimhoff and Beunker2. They showed that the strongest VUV transition below 145 nm involves a third tier 1 ∑ u + ion-pair valence state dissociating to Cl+(1Dg) + Cl-(1Sg), which interacts with the near isoenergetic 4pπ 1 ∑ u + Rydberg state leading to the formation of a double well potential curve, labelled 1 1 ∑ u + .