title: Surface self-diffusion of an organic glass.
abstract: Surface self-diffusion has been measured for an organic glass for the first time. The flattening of 1000 nm surface gratings of liquid indomethacin occurs by viscous flow at 12 K or more above the glass transition temperature and by surface diffusion at lower temperatures. Surface diffusion is at least 10(6) times faster than bulk diffusion, indicating a highly mobile surface. Our data suggest that surface diffusion is the leading mechanism of surface evolution for organic glasses at micrometer to nanometer length scales.
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: L
authors.initials: L
authors.lastname: Zhu
authors.forename: C W
authors.initials: CW
authors.lastname: Brian
authors.forename: S F
authors.initials: SF
authors.lastname: Swallen
authors.forename: P T
authors.initials: PT
authors.lastname: Straus
authors.forename: M D
authors.initials: MD
authors.lastname: Ediger
authors.forename: L
authors.initials: L
authors.lastname: Yu
mesh_terms: D004058:Diffusion; D005898:Glass / Q000737:chemistry*; D007213:Indomethacin / Q000737:chemistry*; D007700:Kinetics; D009930:Organic Chemicals / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D009930:Organic Chemicals; D007213:Indomethacin