We have collected fluorescence data of PPh3 protected Au nanoparticles supported on an anatase surface at the Au L3 edge, which provides some decent looking exafs and seems to fit a bulk gold model rather well (there seems to be agglomeration on the surface, even with our low loadings). 

We have tried to fit the data using both XFIT and EXAFSPAK, but the strange thing is that the exafs oscillations have a huge amplitude, up to 80 in some cases.  Because of this, the only way to fit the data while maintaining sensible Debye-Waller factors is to allow SO2 to become quite large, or to allow the coordination numbers to become very large.

We have spoken to a few others in the field and they have yet to be able to rationalize why there is such a large signal.

I have attached an example of one of the data sets with very large amplitude, if anyone would be willing to take a look at the data it would be much appreciated.

Cheers,

Jason
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Jason F. Alvino