Fig. 3
From: Altered chemistry of oxygen and iron under deep Earth conditions
High-pressure XES spectra of pyrite-structured FeO2Hx at 300 K. The integrated intensity of the XES spectra was normalized to unity. Inset: the \(K_\beta ^\prime\) satellite emission peak between 7030 and 7048 eV after the iron main emission peaks was aligned to that at 133 GPa. The changes of the satellite peak intensity in FeO2Hx are attributed to the high-spin to low-spin transition, as the disappearance of the satellite peak has been used as a robust criterion for the electronic spin-pairing transition of iron in other iron-bearing compounds30
