This proposal seeks to develop the technique of multinuclear RF decoupling and apply it to the study of lithium ion mobility in Lithium Hydroxide. Key to the understanding of existing high temperature data is the assumption that the muon is stabilised to high temperatures by binding to an O2- ion (proton vacancy). Selective RF decoupling of the 7Li and 1H in separate experiments is proposed to determine their indivual contributions to the measured linewidth which, in combination with calculations of the dipolar field, will provide a valuable confirmation of the muon site. The successful conclusion of this experiment will yield an important technical development that should be of general interest to facility users.