EVIDENCE FOR LOCALIZED 4F STATES IN ALPHA-CE

Paramagnetic spectra of gamma and alpha-Ce measured at the same temper ature using high-energy neutrons (approximately 2 eV) yield a 4f occup ancy of approximately 0.8 in alpha-Ce. This phase of Ce also shows sin gle-ion magnetic response but with a high Kondo energy of approximatel y 1800 K. In gamma-Ce we observe the F-2(5/2)-->F-2(7/2) spin-orbit (S O) excitation at approximately 260 meV. Remarkably, alpha-Ce also reve als a broad SO excitation shifted to a higher energy (approximately 45 0 meV). These observations reinforce the idea of localized 4f states i n alpha-Ce and k-f hybridization as the driving mechanism for the gamm a <----> alpha transition.