Magnetic circular dichroism study of the 2S→2P spectrum of matrix-isolated copper atoms

Abstract

The magnetic circular dichroism of the ²S→²P transition of copper atoms isolated in Ne, Ar, Kr, Xe, N₂ and CH₄ matrices has been measured. The spectra are discussed in the light of three current hypotheses concerning the origin of the observed extra splitting of the absorption bands.

The m.c.d. spectra provide no support for the “exciplex” model but they are quite compatible with the “crystal-field” and “Jahn–Teller” interpretations of the splitting.

The order of the ²S→²P_1/2 and ²S→²P_3/2 states is reversed in the Xe matrix as compared with all other hosts and this observation is interpreted in terms of molecular orbital formation involving Cu 4p and Xe 5p atomic orbitals.