Thomas Markland

Professor Thomas Markland, Stanford University.  "Nuclear and electronic quantum fluctuations in hydrogen bonded systems:  From atmospheric science to enzyme catalysis. Woodward CCB Departmental Colloquium.Abstract:   Over the past decades molecular simulation has become an increasingly important tool in interpreting and predicting chemical processes. Inherent in these simulations is the assumption that the nuclei behave classically. However, nuclear quantum effects, such as zero-point energy and tunneling, can dramatically alter the structure and dynamics of systems containing light atoms, such as hydrogen. Including these effects has traditionally required simulations with a computational cost at least two orders of magnitude greater than treating the nuclei classically, prohibiting their use for most applications. In this talk I will discuss our recent developments that allow for the exact inclusion of nuclear quantum fluctuations at negligible computational cost. These simulations, which incorporate the quantum nature of the electrons and nuclei, allow us to elucidate chemical and biological processes ranging from the atmospheric separation of hydrogen isotopes, which are a major input to climate models, to proton delocalization in enzyme active site extended hydrogen bond networks.