EPR studies of excited state exchange and crystal-field effects in rare earth compounds. [Pnictides]

Conference · Thu Jan 01 04:00:00 EST 1976

OSTI ID:7359006

Huang, C Y; Sugawara, K; Cooper, B R

EPR in excited crystal-field states of Tm/sup 3 +/, Pr/sup 3 +/, and Tb/sup 3 +/ in singlet-ground-state systems and in the excited state of Ce/sup 3 +/ in CeP are reviewed. Because one is looking at a crystal-field excited state resonance, the exchange, even if isotropic, does not act as a secular perturbation. This means that one obtains different effects and has access to more information about the dynamic effects of exchange than in conventional paramagnetic resonance experiments. The Tm and Pr monopnictides studied are paramagnetic at all temperatures. The most striking feature of the behavior of the GAMMA/sub 5//sup (2)/ EPR in the Tm compounds is the presence of an anomalous maximum in the temperature dependence of the g-factor. The relationship of this effect to anisotropic exchange is discussed. The results of the EPR of the excited GAMMA/sub 5//sup (2)/ level of Tb/sub 3//sup +/ (g-factor becomes very large at T/sub N/ in antiferromagnetic TbX (X = P, As, Sb) and that of the excited GAMMA/sub 8/ level of Ce/sup 3 +/ in antiferromagnetic CeP will also be reported. For sufficient dilution of the Tb/sup 3 +/ in the terbium monopnictides, the systems become paramagnetic (Van Vleck paramagnets) down to 0/sup 0/K. The Tb/sup 3 +/ excited state resonance EPR in Tb/sub 0.1/ La/sub 0.9/P was studied as an example of behavior in such systems. 10 fig.

• Research Organization: Los Alamos Scientific Lab., N.Mex. (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 7359006
• Report Number(s): LA-UR-76-1567; CONF-760920-1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
360603* -- Materials-- Properties
CRYSTAL FIELD
DOCUMENT TYPES
ELECTRON SPIN RESONANCE
ENERGY LEVELS
EXCHANGE INTERACTIONS
EXCITED STATES
INTERACTIONS
MAGNETIC RESONANCE
PNICTIDES
RARE EARTH COMPOUNDS
RESONANCE
REVIEWS