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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Fivefold symmetry is incompatible with the translational order in all 17 plane groups and is therefore of fundamental interest for two dimensional crystallization processes. A model study on single crystal surfaces, e.g. Cu(111), has been carried out to better understand the fundamental principles of intermolecular interactions between fivefold symmetric corannulene and its derivatives in two-dimensional clusters and lattices, including those consisting of fivefold bowl-shaped (buckybowl) molecules. Rational molecular design and state of the art surface science methods, e.g. Scanning Tunneling Microscopy, Low Energy Electron Diffraction, X-Ray Photoelectron Spectroscopy, Ultraviolet Photoelectron Spectroscopy, Temperature Programmed Desorption, and Reflection Adsorption Infrared Spectroscopy were applied. Several reversible surface phases were identified, including stripes, zig-zag, rosette and rotator phases. The packings of fivefold symmetric molecules was found to exhibit the same patterns upon adsorption as identified in the closest packings of hard pentagons and five-pointed stars.
