XPS Studies of Bonding in Glass

Careful sample preparation is critical for obtaining useftil structural information from surface-sensitive techniques such as XPS. We have found that fracturing the glass sample in vacuum immediately before analysis produces a surface with a structure and composition that is most representative of the bulk. For reasons aheady outlined, polished samples or samples exposed to the ambient have compositionally and structurally altered surfaces that yield misleading results. Surfaces that are created by inert ion sputtering in vacuum also are altered relative to the bulk. 

Note that Equation 6.1 also works for divalent oxides (R O) added to P2O5. 

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