Abstract

We present a first-principles computational study of the interaction of an H atom with the (010) surface of forsterite (Mg2SiO4). Periodic DFT-GGA calculations (PBE) are carried out using the SIESTA code with core pseudopotentials and TZP localized basis sets. Potential energy curves are determined for the approach of the H atom toward different sites of the surface: atop, near, or in between the O, Mg, and Si atoms. An outer adsorption well is found for all investigated sites; it is deepest (162 meV) at a so-called “displaced Mg–O bridge” position. The binding at this well is of the “weak chemisorption”/“strong physisorption” type. An inner stronger chemisorption well (670 meV deep) exists exclusively near an O site but not strictly atop. Depending on the path, we find activation barriers (25–170 meV high) against chemisorption, the lowest of these occurs for the top O site. General trends of the computed interaction energies qualitatively agree with the QM/MM results of Goumans et al. [Mon. Not. R. Astr...

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.