Abstract

The 5-parameter Morse potential (5-MP) of an O – Pd system and the improved extended LEPS potential of an O 2– Pd system were constructed. The adsorption and dissociation of oxygen atoms and oxygen molecules on flat and stepped palladium single crystal surfaces were studied detailedly, and the data of adsorption sites, adsorption geometry, binding energy, eigenvibration, dissociative mechanism, etc. were obtained. Theoretical results show that the high-symmetry sites are the preferred adsorption sites for tilted adsorption of oxygen molecules, and the tilted angle depends on the number of atoms per unit surface area. Meanwhile, a variety of dissociation pathways are analyzed in detail related to the O 2– Pd (111) system. These results show that the adsorptive dissociation of oxygen molecules on the Pd (111) hollow site is precursor-mediated, on the Pd (111) bridge site is direct dissociation and on the Pd (111) top site is not only depended on the translational energy, but also depended on the vibrational energy. Moreover, the role of the step defect for oxygen atoms and oxygen molecules is also discussed related to flat surface. Theoretical results are in good agreement with the experimental results, and explain well the divergence [N. Salanov and V. N. Bibin, Surf. Sci.441 (1999) 399; P. D. Nolan, B. R. Lutz, P. L. Tanaka and C. B. Mullins, Surf. Sci.419 (1998) L107] related to the O 2 dissociation mechanism.

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.