The dielectric response of Gd3+ ion-doped PbWO4 single crystal in wide temperature and frequency ranges was measured and a new dielectric relaxation phenomenon relative to O ion was observed during the cooling process. With experimental results of X-ray photoelectron spectroscopy, the existence of interstitial O ions was verified in Gd-doped crystals.

Verification of Interstitial Oxygen in Gd:PbWO4. H.W.Huang, Z.G.Ye, M.Dong, W.L.Zhu, X.Q.Feng: Japanese Journal of Applied Physics - 2, 2002, 41[6B], L713