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Can electron energy-loss spectroscopy (EELS) be used to quantify hydrogen in minerals from the O K edge?

2009; Mineralogical Society of America; Volume: 95; Issue: 1 Linguagem: Inglês

10.2138/am.2010.3290

1945-3027

Lawrence A.J Garvie,

X-ray Spectroscopy and Fluorescence Analysis

The proposition has been made and is now gaining popular acceptance that electron energy-loss spectroscopy (EELS) attached to a transmission electron microscope (TEM) can be used to semiquantitatively measure H in minerals-specifically, that there is a pre-peak to the O K edge near 530 eV whose intensity is a measure of H concentration in OH- and H2O-bearing minerals. I show here that the O K edges from H-bearing minerals, free of electron-beam damage, lack a peak near 530 eV. Instead, under electron irradiation in the TEM, a transient peak near 530 eV can form in H-bearing as well as anhydrous minerals. The intensity of the transient peak is dependent on total fluence and fluence rate. The origin of the radiation-induced peak at 530 eV is from O2 liberated during damage by the incident electron beam. In conclusion, there is no evidence for an OH peak near 530 eV from H-bearing minerals.