Electron paramagnetic resonance of Eu2+in the alkali iodides

摘要

The electron paramagnetic resonance of divalent europium impurity in the isomorphic cubic hosts of NaI, KI and RbI has been observed at Xhyphen;band frequencies. The spinhyphen;Hamiltonian parameters for EU2+in orthorhombic sites of NaI, KI, and RbI have been determined at 94 and 300 K. The dominant second order spinhyphen;Hamiltonian parameterb02for the observed symmetry was found to be positive for all sodium, potassium and rubidium iodides at liquid helium temperatures. The behavior of theb02term with lattice size in the alkali iodide series is discussed on the basis of the one observed for the chlorides and bromides. Considerable disagreement between the spinhyphen;Hamiltonian parameters for Eu2+in KI obtained in this work and those previously reported by Poret and Lambert is noted.