BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:The diffusion of benzene adsorbed on graphite surfaces studied wit
 h quasi-elastic neutron scattering (QENS) techniques - Irene Calvo-Almazá
 n\, Institut Laue Langevin\, Grenoble\, France
DTSTART:20140424T150000Z
DTEND:20140424T160000Z
UID:TALK51517@talks.cam.ac.uk
CONTACT:Stephen Walley
DESCRIPTION:In this work we aim to understand the microscopical mechanisms
  of diffusion and friction of benzene molecules on graphite surfaces - a s
 imple model system that shows\, nevertheless\,  a wealth of phenomena that
  depend on\, e.g.\, coverage and temperature [1]. Quasi-elastic neutron sc
 attering (QENS) spectroscopy yields novel insights in the diffusive behavi
 or of benzene\, C6H6\, adsorbed on the basal plane [0001] of graphitic sub
 strates. Our extensive study of the diffusion for a wide range of coverage
 s\, from 0.1 to 1.0 monolayers (ML)\, and temperatures\, from 60K to 140K\
 , reveals that intermolecular interactions play an essential role in the s
 urface dynamics of molecules. The rough binary collision model [2\,3] betw
 een adsorbates provides values for the friction parameters in agreement wi
 th the experimental results\, indicating that molecules behave as hard dis
 ks and that a significant part of the origin of friction lies in the excha
 nge of linear and angular momentum between them through binary collisions.
  \n\n[1] H. Hedgeland et al.\, Nature Physics 5 (2009) 561 – 564 \n\n[2\
 ,3] D. Chandler\, J. Chem. Phys. 60\, 3500 (1974)\;  D. Chandler\, J. Chem
 . Phys. 60\, 3508 (1974).
LOCATION:Mott Seminar Room\, Cavendish Laboratory
END:VEVENT
END:VCALENDAR