Abstract
Anomalous resonance lines in the EPR spectrum of thulium ethyl sulfate single crystals at 4.2°K were investigated at three microwave frequencies, 9, 25, and 35 GHz. It is shown that the resonance absorption occurred from Tm3+ (4f12, 3H6) ions located at a site of local symmetry of C2v or lower, rather than at the normal C3h site. The symmetry axes of the defect sites were found to lie in the mirror plane of the normal sites and to be spaced 120° apart in this plane. Two distinct types of defects having these general characteristics were found and suggestions for these structures are made. Spin-Hamiltonian parameters for each type site are reported, as are values for Tm3+ in the Y2(SO4)3· 8H2O lattice. It is shown that the ground states for both sites are of μ=0 type and consist mainly of MJ=± 6.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
