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Quantum mechanics reveals how perfluoropolyether molecules can lower flying height.
With the advent of faster computers and the ready availability of "parallel" computer codes that allow various parts of a calculation to be carried out simultaneously, it has become feasible to perform quantum-mechanical calculations for physically realistic systems.
This ability has been exploited in many areas of physics and chemistry. For example, quantum mechanics has been used to calculate the elastic properties of materials from the change in energy caused by applying a strain. It is used extensively by chemists to calculate the thermodynamics of reactions and even reaction activation energies.
It is surprising that such methods have not been used to any great extent to understand tribological phenomena until now. Quantum calculations were recently used by Robert Waliman of Hitachi Global Storage Technologies in San Jose, Calif., to explore the bonding and dynamics of a novel class of lubricants for hard-disk drives, consisting of hydroxyl-terminated perfluoropolyethers (PFPE), known as TA-30 and invented by Daisuke Shirakawa and colleagues of the Asahi Glass Co.,...