J. Phys. IV France 10 (2000) Pr7-157-Pr7-160
Dynamics of intermediate-length alkane films absorbed on graphiteK.W. Herwig1, D. Fuhrmann1, L. Criswell1, H. Taub1, F.Y. Hansen1, R. Dimeo2 and D.A. Neumann1
1 Argonne National Laboratory, IPNS, Bldg. 360, 9700 S. Cass Avenue, Argonne, IL 60439, U.S.A.
2 National Institute of Standards and Technology, NIST Center for Neutron Research, 100 Bureau Drive - Stop 8562, Gaithersburg, MD, U.S.A.
The dynamics of flexible chain molecules near a solid interface is of fundamental interest in polymer science. This paper makes a preliminary report on a quasielastic neutron scattering study of the dynamics of monolayer films of C 24H50 adsorbed on graphite. Quasielastic scattering was observed at temperatures as low as ≈ 180K, well below the monolayer melting temperature of 340 K. Preliminary analysis of the data indicates that at 230 K the entire molecule executes a rolling motion about its long axis while the terminal methyl groups exhibit relatively rapid reorientation.
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