Investigation of the interaction of some astrobiological molecules with the surface of a graphite (0001) substrate. Application to the CO, HCN, H2O and H2CO molecules

TL;DR

This study uses semi-empirical calculations to explore how molecules like CO, HCN, H2O, and H2CO interact with graphite surfaces, revealing their preferred adsorption sites, energies, and diffusion behaviors relevant to astrobiology.

Contribution

It provides detailed potential energy surfaces and adsorption characteristics for key astrobiological molecules on graphite, a novel application in surface interaction modeling.

Findings

Identified equilibrium adsorption sites for each molecule.

Calculated adsorption energies for CO, HCN, H2O, and H2CO.

Determined diffusion constants for molecular surface mobility.

Abstract

Detailed semi-empirical interaction potential calculations are performed to determine the potential energy surface experienced by the molecules CO, HCN, H2O and H2CO, when adsorbed on the basal plane (0001) of graphite at low temperature. The potential energy surface is used to find the equilibrium site and configuration of a molecule on the surface and its corresponding adsorption energy. The diffusion constant associated with molecular surface diffusion is calculated for each molecule.