Member of Yale faculty since 2018
Research in the Hammes-Schiffer group centers on the development and application of theoretical and computational methods for describing chemical reactions in condensed phases and at interfaces. Our overall objective is to elucidate the fundamental physical principles underlying charge transfer reactions, dynamics, and quantum mechanical effects in chemical, biological, and interfacial processes. Our research encompasses the development of analytical theories and computational methods, as well as applications to a wide range of experimentally relevant systems. The group is divided into three general areas: proton-coupled electron transfer reactions, enzymatic processes, and non-Born-Oppenheimer electronic structure methods.
Proton-coupled electron transfer (PCET) reactions play a critical role in a wide range of chemical and biological processes. We have developed a general theory for PCET, which allows the calculation of rate constants and deuterium kinetic isotope effects, and have applied this theory to experimentally studied reactions in solution, proteins, and electrochemistry. We have also developed methodology to simulate the nonadiabatic ultrafast dynamics of photoinduced PCET reactions. Applications of these theories have assisted in the interpretation of experimental data and provided experimentally testable predictions. Our calculations have also guided the design of molecular electrocatalysts and photocatalysts for energy conversion devices such as solar cells. Current applications within the group center on PCET in photoreduced metal-oxide nanocrystals, artificial photosynthetic systems, electrode/solution interfaces, and photoreceptor proteins.
Our studies of enzymatic processes have focused on the catalytic roles of protein motion, hydrogen bonding, hydrogen tunneling, electrostatics, conformational sampling, and metal ions. To study these properties, we have developed hybrid quantum/classical molecular dynamics approaches, as well as methods for calculating the vibrational shifts of nitrile probes in enzyme active sites. Current applications within the group include DNA polymerases, ribozymes, and various metalloenzymes.
Our group has also developed the nuclear-electronic orbital (NEO) method for incorporating nuclear quantum effects and non-Born-Oppenheimer effects into electronic structure calculations. In the NEO approach, specified nuclei are treated quantum mechanically on the same level as the electrons using molecular orbital techniques. Our current focus is on the development of multicomponent density functional theory (NEO-DFT), which treats both electrons and specified protons quantum mechanically with a proper description of electron-electron and electron-proton correlation effects. This method includes proton delocalization and zero point energy directly into geometry optimizations, reaction paths, and dynamics and avoids the Born-Oppenheimer separation between electrons and protons in a computationally practical manner. An analogous time-dependent DFT approach, NEO-TDDFT, enables the calculation of excited electron-proton vibronic states.
B.A. Chemistry, Princeton University, 1988
Ph.D. Chemistry, Stanford University, 1993
Postdoctoral Fellow, AT&T Bell Laboratories, 1993-95
National Science Foundation CAREER Award, 1996
Ralph E. Powe Junior Faculty Enhancement Award, Oak Ridge Associated Universities, 1998
Alfred P. Sloan Research Fellowship, 1998
Camille Dreyfus Teacher-Scholar Award, 1999
Deputy Editor and Senior Editor of Journal of Physical Chemistry A/B/C/Letters, 2001-2014
National Science Foundation Creativity Extension Award, 2003
Alexander M. Cruickshank Lecturer, Gordon Research Conferences, 2004
Iota Sigma Pi Agnes Fay Morgan Research Award, 2005
International Academy of Quantum Molecular Science Medal, 2005
American Chemical Society Akron Section Award, 2008
Fellow of American Physical Society, 2010
National Institutes of Health MERIT Award, 2011
Fellow of American Chemical Society, 2011
Chair of ACS Division of Physical Chemistry, 2012
Member of American Academy of Arts and Sciences, 2012
Fellow of American Association for the Advancement of Science, 2013
Member of U.S. National Academy of Sciences, 2013
Member of International Academy of Quantum Molecular Science, 2014
Editor-in-Chief of Chemical Reviews, 2014-present
Fellow of Biophysical Society, 2015
Board of Reviewing Editors for Science, 2016-present
Senior Fellow of Canadian Institute for Advanced Research (CIFAR), 2016-present
G.M. Kosolapoff Award from Auburn University, 2019