PARAMAGNETIC RESONANCE IN METALLIC EUROPIUM AND INTERMETALLIC COMPOUNDS

The results are reported of paramagnetic resonance experiments on Eu metal and the intermetallics EuIr/sub 2/ and GdIr/sub 2/ carried out in a millimeter wave spectrometer. The resonance line in Eu metal occurs at g = 1.985 plus or minus 0.015, which cannot be explained from the behavior of Eu/sup 3+/. This experiment confirms the metallurgical and magnetic evidence for the divalent state of Eu. No resonance was detected in EuIr/sub 2/ which crystallizes in the cubic Laves phase (C15). From its lattice constant Eu was concluded to be in the trivalent state. The resonance in GdIr/sub 2/, trivalent state, increases with decreasing temperatures to below the Curie point, where the resonance broadens to a point where observation is no longer feasible. (B.O.G.)