2026 Program
Event: Elizabeth Bartlett (University of Kansas) and Carlos Baiz (University of Texas at Austin)
When: May 15th, 2026
12-1 PM EST
Registration Link
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Early Career Talk: “A New Theory for Activation Energy Calculations”
Elizabeth Bartlett (University of Kansas)
Biography:
Elizabeth Bartlett is a Ph.D. candidate in the Department of Chemistry at the University of Kansas. She completed her B.A. in chemistry and computer science at the College of Saint Benedict. Bartlett is currently in the research group of Prof. Ward Thompson, where her research focuses on developing and applying theoretical methods to provide molecular-level insight into the fundamental behavior of condensed phase systems.
Abstract:
For over a century, activation energy calculations have dominantly employed the Arrhenius approach, yet in experiment and molecular simulation this presents many limitations. Recently, we introduced a new theory that connects the dynamics of thermodynamic ensembles, enabling activation energies of rate constants and other dynamical timescales to be calculated efficiently from single-temperature simulations. This theory connects how the equilibrium fluctuations in energy of a single constant-temperature system are correlated with the dynamics to extract activation energies and non-Arrhenius effects. In the same spirit, the theory is extended to determine activation volumes using the correlation between the dynamics and the equilibrium volume fluctuations at constant pressure. We apply the theory to condensed phase systems, including neat water, demonstrating a more efficient route to activation parameters with enhanced mechanistic insight into the driving forces of dynamics.
Talk: “Modulating Interfacial Hydrogen-Bond Networks using Cosolvents and Electrode Potential”
Prof. Carlos Baiz (University of Texas at Austin)
Biography:
Carlos Baiz is the William H. Wade Endowed Associate Professor of Chemistry at the University of Texas at Austin. His lab studies the biophysics of complex systems, including biocondensates, crowded environments, heterogeneous lipid membranes, membrane proteins, and electrochemical interfaces, using ultrafast two-dimensional infrared (2D IR) spectroscopy, near-field IR microscopy, and molecular dynamics simulations.
Abstract:
Interfacial solvent structure and dynamics govern charge transport and selectivity at electrode interfaces. In this talk, Carlos Baiz will describe measurements using surface-enhanced infrared absorption spectroscopy (SEIRAS), surface-enhanced two-dimensional infrared spectroscopy (SE-2D IR), and constant-potential molecular dynamics (MD) to map how the neutral cosolvent dimethyl sulfoxide (DMSO) modulates water’s hydrogen-bond network at gold electrodes under polarization. SEIRAS reveals DMSO enrichment and concomitant interfacial dehydration, alongside signatures of confined water clusters with “buckled” geometries; MD provides the complementary atomistic picture of composition- and potential-dependent changes in hydrogen-bond populations, orientational responses, and local solvation topologies. Together, these results show that cosolvent identity and electrode charge act as orthogonal controls over interfacial solvation without invoking any specific reaction pathway.
To measure interfacial dynamics, the Baiz group employs nitrile-based vibrational probes in SE-2D IR, resolving fast local frequency fluctuations and slower hydrogen-bond rearrangements associated with water donating to the surface-bound reporter. Introducing DMSO accelerates interfacial hydrogen-bond reorganization while maintaining spectral homogeneity at the interface, in contrast to bulk mixtures where microheterogeneity slows structural diffusion. The spectroscopy-simulation agreement establishes a general framework in which neutral cosolvents can selectively disrupt cooperative water networks at metal interfaces and, together with electrode polarization, offer practical levers to tune hydrogen-bond lifetimes, orientations, and connectivity central to physical chemistry at charged metal surfaces.
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