Re-configuration and interaction of hydrogen sites in olivine at high temperature and high pressure | American Mineralogist | GeoScienceWorld
Yang et al. (page 878) carried out in situ high-temperature and high-pressure IR spectroscopic investigations on hydrogen storage sites in the natural olivine and synthetic Fe-free forsterite. The results show that hydrogen does not transfer between storage sites with increasing temperature, but displays disordering at temperatures over 600 °C. In contrast, pressure can induce re-configuration of hydrogen storage sites corresponding to the 3610 and 3579 cm–1 bands. Hydrogen storage sites also exhibit disordering at high pressure. In addition, the dehydrogenation experiments of the natural olivine indicate interactions of hydrogen storage sites. Protons released from titanium-clinohumite defects move to pure Si vacancies, and also to Mg vacancies coupling with trivalent cations. This study is of importance to understand water distribution and its impact on the upper mantle.
Yan Yang, Wendi Liu, Zeming Qi, ZhongPing Wang, Joseph R. Smyth, Qunke Xia; Re-configuration and interaction of hydrogen sites in olivine at high temperature and high pressure. American Mineralogist ; 104 (6): 878–889. doi: https://doi.org/10.2138/am-2019-6921