Electron Paramagnetic Resonance ofEu2+in CaWO4

Abstract

Single crystals of CaW${\mathrm{O}}_4$ doped with ${\mathrm{Eu}}^{2+}$ were investigated by electron paramagnetic resonance at 300, 77, 20, and 4°K. A spectrum of tetragonal symmetry was observed and fitted to the spin Hamiltonian for tetragonal symmetry. The values of the parameters are given for 300, 77, and 20°K. The absolute sign of the parameters was determined from observations at 4°K. The hyperfine splitting constants are $A^{151}=-34.4\mathrm{}\pm 0.5$, $B^{151}=-35.0\mathrm{}\pm 0.5$; $A^{153}=-15.5\mathrm{}\pm 0.3$, $B^{153}=-16.0\mathrm{}\pm 0.3$; all in ${10}^{-4\mathrm{}}$ ${\mathrm{cm}}^{-1\mathrm{}}$.