Adsorption of Oxygen and Nitrogen Atoms on the SiO₂ Surface: Molecular Dynamics Calculation Based on the Quantum-Mechanical Potential

The processes of adsorption of N and O atoms on the surfaces of the thermal protection material SiO₂ are studied by the methods of quantum mechanics and molecular dynamics. The potential energy surface (PES) is calculated using the electron density functional theory. Based on the obtained PESs, the rate constants of adsorption of N and O atoms are determined by molecular dynamics methods in a wide range of surface temperatures of 500–2200 K and presented in the form of a generalized Arrhenius formula. The calculated rate constants are compared with the known phenomenological models and the calculation results based on the transition state theory.