Research Interests

Professor Gellman's group uses a wide variety of experimental techniques to study processes occurring on surfaces. Much of the work involves the use of ultrahigh vacuum methods to study the bonding of molecules to metal surfaces, surface structure, reaction kinetics, catalysis, friction, lubrication, etc.  

The use of surface science methods to create and study well-defined catalytic surfaces allows Professor Gellman's group to investigate problems in heterogeneous catalysis at the most fundamental level. One current project is aimed at understanding the nature of the transition state for elementary steps important in the catalytic surface chemistry. These include reactions such as alkyl hydrogenation, acid deprotonation, ß-hydride elimination, dehalogenation and many others. The experimental measurements to probe the characteristics of the transition state are compared to the results of Density Functional Theory simulations performed in collaboration with Professor Sholl. A second project is aimed at understanding the properties of naturally chiral surfaces used for enantioselective heterogeneous catalysis. Naturally chiral high Miller index metal surfaces were first studied in Professor Gellman’s laboratory and have been shown to have enantiospecific interactions with chiral adsorbates.

Surface science methods are having an important impact in the field of tribology, the study of the mechanical properties of surfaces such as friction, adhesion, and lubrication. A unique apparatus has been developed for study of the frictional properties of single crystalline metal surfaces under highly controlled conditions. Current work is aimed at the study of friction between the Si surfaces used in MEMS devices. Other work is aimed at the study of the surface chemistry of lubricants. Much of this work has focused on the lubrication of data storage media.

Representative Publications

D.M. Rampulla, A.J. Francis, K.S. Knight, A.J. Gellman “Enantioselective surface chemistry of 2-bromobutane on the Cu(643)^R&S and Cu(531)^R&S surfaces” J. Phys Chem. B 110, (2006), 10411-10420

P. Ye, A.J. Gellman, “The transition state for β-hydride elimination in alkyl groups on Pt(111)” J. Phys. Chem. B 110(19), (2006), 9660-9666

J. Horvath, P. Kamakoti, A. Koritnik, D.S. Sholl, A.J. Gellman “Enantioselective Separation on a Naturally Chiral Surface” J. Amer. Chem. Soc. 126(45), (2004), 14988-14994

A.J. Gellman “Vapor Lubricant Transport in MEMS Devices” Tribology Lett. 17(3), (2004), 455-461

A.J. Gellman, K.R. Paserba “Kinetics and Mechanism of Oligomer Desorption from Surfaces: n-Alkanes on Graphite” J. Phys. Chem. 106, (2002), 13231-13241