Ultrahigh-frequency NMR of Tm3+ ions in single crystals of thulium ethylsulfate at high magnetic fields

Abstract

Resonant transitions predicted earlier between low-lying electron-nuclear sublevels of the Tm3+ ground state were observed at frequencies up to 700 MHz in a dielectric Van Vleck paramagnet - thulium ethylsulfate (TmES) single crystal. It is shown that, due to the distortion of the 4f-electron shell of rare-earth ion in an applied magnetic field, the parameters of electron-nuclear interaction become field dependent. Experimental results of second moment of Tm3+ enhanced NMR line in TmES are presented. The possible mechanisms of line broadening are considered, particularly as a result of the first excited doublet splitting. © 2003 Elsevier B.V. All rights reserved.