A theoretical study of the structures of propylene adsorbed on the Si(100)-(2 × 1) surface

• Published in: Surface science Vol. 298; no. 1; pp. 87 - 93
• Main Author: Craig, B.I.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 10.12.1993; Amsterdam Elsevier Science; New York, NY
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Physics; Solid surfaces and solid-solid interfaces; Surface structure and topography; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Propylene; Surfaces; Silicon; Adsorption; Polymers; Surface structure
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(93)90083-V

The adsorption of propylene, C 3H 6, on the Si(100)-(2 × 1) surface is examined. The adsorbed structure is obtained from minimising the total energy with respect to variations in the atomic coordinates of the adsorbed molecule and the first four silicon layers of the underlying substrate. Two similar values for a local minimum in the total energy, each corresponding to a different adsorbed structure, are found by this process. One structure maintains both the C 3H 6 molecule and the underlying Si dimer, while the other structure is formed from the breaking of one C-H bond and the underlying Si dimer. These two structures correlate with the experimentally observed characteristics of adsorbed C 3H 6 on Si(100) where 35% of the propylene can be desorbed on heating and the remaining 65% is dissociated. The two structures of adsorbed C 3H 6 can be compared with the previously determined structures of C 2H 2, C 2H 4 and C 6H 6 on Si(100) to give a more general description of the structures derived from the adsorption o unsaturated hydrocarbons on the Si(100) surface.