Nazabal V, Fargin E, Le Flem G, Briois V, Moulin C C, Buffeteau T, Desbat B
I.C.M.C.B., (UPR 9048), Pessac, France.
J Synchrotron Radiat. 2001 Mar 1;8(Pt 2):788-90. doi: 10.1107/s090904950001829x.
O-K edge XANES spectroscopy evidences structural modification induced by thermal poling treatment in surfaces of bulk Herasil silica glass presenting second harmonic generation. Considering model silicon dioxide clusters, calculations based on full multiple scattering approach have been performed in order to explain accurately the differences observed on XANES spectra at different stage of the poling treatment. These structural modifications on extreme surface affect both network and defects by breaking Si-O-Si bridging bonds. Despite of the formation of bridging bond occurring during the thermal depoling -which erases the SHG inside the glass-, the initial structure of the unpoled sample is not reproduced.
O-K边X射线吸收近边结构光谱证明，具有二次谐波产生特性的块状赫拉西尔石英玻璃表面经热极化处理后发生了结构改性。考虑到二氧化硅模型团簇，基于全多重散射方法进行了计算，以准确解释在极化处理不同阶段的X射线吸收近边结构光谱中观察到的差异。极端表面上的这些结构改性通过破坏Si-O-Si桥键影响网络和缺陷。尽管在热退极化过程中会形成桥键（这会消除玻璃内部的二次谐波），但未极化样品的初始结构并未重现。
