Electron spin resonance of rare earth ions in metallic beryllides: crystalline field 'single-ion' effects

Abstract

The effects of a low lying Gamma ₈⁽¹⁾ excited state on the ESR properties of the ground state Gamma ₇ doublet are demonstrated for the rare earth ions Er and Dy in the beryllides LaBe₁₃, LuBe₁₃ and ThBe₁₃. The analysis of the authors' ESR results yields a rough estimate of the Gamma ₇- Gamma ₈⁽¹⁾ splitting. Further, the ESR data, including those of Gd in the same hosts, suggest the near independence of the localised conduction electron coupling on the rare earth 4f occupation number.