Determination of Hydrogen Atoms Position in Enstatite by IR Spectra

Abstract

We have calculated the electronic state in enstatite (En, MgSiO₃) using the DFT to understand the hydrous mechanism. Stable positions of hydrogen in En were estimated from the direct comparison of the vibrational frequencies obtained by the experimental FT-IR method and by the first-principles methods. The calculated wavenumber for the structures of conf. Si-1, 2 and Mg-M1, M2 (Figure 2) indicated good agreement to experimental En band. Especially, high wavenumber bands are better reproduced by the structures of conf. Si-1, 2.