MUON IMPLANTATION IN ALKALI-METAL HYDRIDES

Zero, longitudinal and transverse field mu SR measurements have been m ade on LiH, LiD and NaH. The primary motivation for the study was to e lucidate the behaviour of the muons in the diamagnetic state and analy sis of the time-dependent zero field relaxation data suggests that neg atively charged muonium, Mu(-), is formed and takes up a H- vacancy si te in these materials. Evidence is presented for a small (approximatel y 2%) reduction in the Mu(-)-Li distance relative to the unperturbed n earest neighbour anion-cation distances in the pure crystal lattices.