Feng, XQ (reprint author), Chinese Acad Sci, Shanghai Inst Ceram, State Key Lab High Performance Ceram & Superfine, Shanghai 200050, Peoples R China.
To elucidate the annealing process in air, optical absorption spectroscopy, X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) measurements are conducted in PbWO4 crystals annealed in air at different temperatures. The annealing exhibits a complex phenomenon, but the essence is the exchange of oxygen components between the crystal and environment to modify the intrinsic defects in the crystal. Interstitial oxygen ions are found to play an important role in the process for the influence on the 350 nm absorption band. The mechanism of annealing is discussed in this paper. (C) 2002 Elsevier Science B.V. All rights reserved.