SUBMILLIMETER EPR SPECTROSCOPY OF LANTHANIDE COMPOUNDS - PAIR CENTERSOF HO3+ IN CSCDBR3

High-frequency EPR spectra corresponding to magnetic dipole transition s between the doublet-singlet-doublet group of the lowest crystal fiel d levels of the trigonal single ion and the symmetric dimer centers in CsCdBr3 have been studied. For the dimer center, the absorption spect ra in the manifold of the lowest 1024 electron-nuclear states are simu lated by successive diagonalization of the electron-nuclear Hamiltonia n which includes the crystal field, the electronic Zeeman energies, th e magnetic and quadrupole hyperfine interactions, and the dipole-dipol e interactions between the paramagnetic ions. The crystal field parame ters of Ho3+ ions in the symmetric dimer are determined. (C) 1998 Else vier Science S.A.