Muon-spin spectroscopy in selenium

In recent years, the positive muon, used as a chemical analogue of the prot on, has proven of great value in studies of the behaviour of hydrogen defec ts in semiconductors, especially the Group IVA elements Si and Ge. In the p resent work we explore the application of the mu SR techniques to the Group VIA semiconductors S and Se, reporting new data for Se and comparing these with previous data for S. The chemical species formed following muon impla ntation include two paramagnetic centres, namely atomic muonium and a molec ular radical, together with one or more muon states which appear electronic ally diamagnetic. The reaction schemes are evidently similar in the two ele ments although there are significant quantitative differences in the kineti cs. The very close similarity in the muon-electron hyperfine constants of t he radical states tends to support their assignment to the simple diatomic species SeMu and SMu, close relatives of the hydroxyl radical OH. Copyright (C) 2000 John Wiley & Sons, Ltd.