24th Annual Stauffer Lectureship (Day 2 of 2): Professor Sharon Hammes-Schiffer, Yale University

24th Annual Stauffer Lectureship (Day 2 of 2): Professor Sharon Hammes-Schiffer, Yale University (Host: Lynette Cegelski and Tom Markland)

About the Seminar

"Multicomponent Quantum Chemistry: Integrating Electronic and Nuclear Quantum Effects"

Nuclear quantum effects such as zero point energy, nuclear delocalization, and tunneling play an important role in a wide range of chemical processes. Typically quantum chemistry calculations invoke the Born-Oppenheimer approximation and include nuclear quantum effects as corrections following geometry optimizations. The nuclear-electronic orbital (NEO) approach treats select nuclei, typically protons, quantum mechanically on the same level as the electrons with multicomponent density functional theory (DFT) or wavefunction methods. Recently electron-proton correlation functionals have been developed to address the significant challenge within NEO-DFT of producing accurate proton densities and energies. Moreover, time-dependent DFT and related methods within the NEO framework have been developed for the calculation of electronic, proton vibrational, and electron-proton vibronic excitations. An effective strategy for calculating the vibrational frequencies of the entire molecule within the NEO framework has also been devised and has been shown to incorporate the most significant anharmonic effects. Furthermore, multicomponent wavefunction methods based on coupled cluster and configuration interaction approaches have been developed within the NEO framework. These combined NEO methods enable the inclusion of nuclear quantum effects and non-Born-Oppenheimer effects in calculations of proton affinities, pKa’s, optimized geometries, vibrational frequencies, isotope effects, minimum energy paths, reaction dynamics, excitation energies, tunneling splittings, and vibronic couplings for a wide range of chemical applications.

About the Speaker

Sharon Hammes-Schiffer received her B.A. in Chemistry from Princeton University in 1988 and her Ph.D. in Chemistry from Stanford University in 1993, followed by two years at AT&T Bell Laboratories.  She was the Clare Boothe Luce Assistant Professor at the University of Notre Dame from 1995-2000 and then became the Eberly Professor of Biotechnology at The Pennsylvania State University until 2012, when she became the Swanlund Professor of Chemistry at the University of Illinois Urbana-Champaign.  Since 2018, she has been the John Gamble Kirkwood Professor of Chemistry at Yale University.  She is a Fellow of the American Physical Society, American Chemical Society, American Association for the Advancement of Science, and Biophysical Society.  She is a member of the American Academy of Arts and Sciences, the U.S. National Academy of Sciences, the International Academy of Quantum Molecular Science, and the Basic Energy Sciences Advisory Committee.  She was the Deputy Editor of The Journal of Physical Chemistry B and is currently the Editor-in-Chief of Chemical Reviews.  She is on the Board of Reviewing Editors for Science and has served as Chair of the Physical Division and the Theoretical Subdivision of the American Chemical Society. She has over 250 publications, is co-author of a textbook entitled Physical Chemistry for the Biological Sciences, and has given more than 380 invited lectures.