A molecular dynamics computation was used to study the dynamic behavior of atomic oxygen on a crystalline platinum FCC(111) surface. A Lennard-Jones (12-6) potential function was used to describe pairwise interactions of both substrate (Pt) and adatom (O) interactions. Using published values for the platinum potential, the adatom-substrate interactions were determined by an iterative process. Calculations of resultant frequency spectra were compared to experimental EELS data found in the literature. The simulation based upon the Lennard-Jones potential was able to reproduce the experimental frequency spectrum with good agreement. The model was fit to three different published PtO bond lengths (2.1, 1.98, and 1.91 Å), without altering the frequency spectra; also adsorption energies for the adatom were in accordance with published values. The simulation showed versatility to fit several sets of results suggesting applicability to several experimental environments. Observations were made as to the motion of the adatom on the Pt(111) surface. Diffusion measurements were made as a function of temperature and the results compared to similar work which utilized a different method.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Condensed Matter Physics
- Surfaces and Interfaces