Magnetic circular dichroism and the Jahn-Teller effect in the potassium atom “blue triplet” in krypton and xenon matrices

Abstract

The K/Kr “blue triplet” in the 680–760 nm region ( 2S→ 2P) arises from two major sites, each of which gives rise to a triplet pattern. The experimentally determined excited-state spin-orbit coupling constant is −64 cm −1 from annealing studies, it is possible to deconvolute the absorption and MCD contours of the most important site. These are well simulated by a T 1⊗ (e⊕t 2) cluster model Jahn-Teller (JT) calculation with a JT energy of 835 cm −1 and a single effective frequency, ν=29.8 cm −1. A similar calculation on earlier K/Xe data gives a JT energy of 667 cm −1 and ν=23.8 cm −1. Comparisons are made between alkali-metal parameters in Ar, Kr and Xe hosts.