COLL 72 |
| Seung Soon Jang, Shiang-Tai Lin, Yun Hee Jang, Yong-Hoon Kim, and William A. Goddard III. Materials and Process Simulation Center, California Institute of Technology, Beckman Institute (139-74), Pasadena, CA 91125 |
| The rotaxane has been intensively studied because of its interesting properties which are attributed to the molecular recognition between electron donor and acceptor. Especially, the shuttling motion of electron accepting cyclobis-(paraquat-p-phenylene) (CBPQT4+) between the electron donating stations such as tetrathiafulvalene (TTF) and 1,5-dioxynaphthalene (DNP) moieties has brought many applications for molecular switch in nanoelectronics and for artificial muscle in nanomechanics. For the fabrication of any reliable devices based on such molecules, the self-assembled monolayer (SAM) seems to provide a promising way. Although it has been widely used in this field, the detailed information at molecular level has not been fully understood yet. In this work, we studied the SAM of rotaxane on Au (111) surface using molecular dynamics method. For this purpose, using a density functional theory at B3LYP/6-31G** level as well as experimental observations, we developed a new force field which successfully describes bulk and surface of Au and Au-organics thiol interaction. The interaction between organic molecules in this system was simulated using Dreiding which is generic force field. After equilibrating SAM structure with surface coverage, the SAM formation energy and structure were analyzed. In addition, the vibrational modes of rotaxane molecules in SAM was characterized and compared with those of isolate rotaxane molecule. |
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Nanoscience and Nanotechnology
2:00 PM-5:15 PM, Sunday, March 28, 2004 Marriott -- Grand Ballroom K, Oral
Division of Colloid and Surface Chemistry |