Hi,

Looking at the notes from one of Bruce Ravel’s 2000 EXAFS courses, I noticed that you used EuTiO3 as an example. My understanding is that this is a Eu++ compound; yet the resonance peak in the XANES spectrum occurs spot on where I would expect Eu+++ to be, around 6982 eV. As the table below shows (from Rakovan, J., Newville, M., and Sutton, S. (2001) Evidence of heterovalent europium in zoned Llallagua apatite using wavelength dispersive XANES. American Mineralogist, 86, 697-700), the location of the Eu++ resonance peak does not seem to vary much from compound to compound.

I’m also joining a figure showing the XANES L3 Eu spectra of EuTiO3 together with other compounds. The Std spectra shown for comparison are for mixtures of Eu2O3, W, and WO3 cooked at 1200C in an inert atmosphere, and prepared so that sample StdB has 20% Eu++, and sample stdC 50% Eu++ (the final product is a mixture of EuWO4 and Eu2(WO4)2). The growing peak at 6974 corresponds to Eu++.

Any thought about this discrepancy? Where are the data published?

Thanks in advance for you help,

All the best as ever, JOEL


Ps – I cc’d to Bruce Ravel’s email address as I don’t think that the list takes attachments or embedded figures...




Rakovan, J., Newville, M., and Sutton, S. (2001) Evidence of heterovalent europium in zoned Llallagua apatite using wavelength dispersive XANES. American Mineralogist, 86, 697-700.