Statistical Thermodynamics & Molecular Simulations (STMS) Seminar Series: Prof. Jeffrey Potoff (Wayne State) and Dr. Subhajyoti Chaudhuri (Northwestern)
These seminar series are aimed at providing a virtual platform for sharing scientific research in the area of statistical mechanics, molecular simulations, and computational materials science. Since early 2020, the coronavirus pandemic has disrupted many large in-person scientific gatherings, including conferences and department seminars. STMS is aimed at filling this gap, and provide a venue for dissemination of research findings and exchange of ideas in the age of COVID. This model is being currently used by several other scientific communities, and can potentially continue even beyond the pandemic if successful.
Each seminar will be a 60-minute event and will comprise of a long-form (30-minute) talk by a principal investigator or a senior research scientists from academia or industry and a short-form (15-minute) presentation by a graduate student or a postdoc. The remainder of the event will be dedicated to Q&A (10 minutes for the PI, 5 minutes for the student/postdoc). Long-form speakers will be chosen by the STMS Organizing Committee, while we encourage suggestions from the community at large. Student and postdoctoral speakers can either be nominated by their advisors or can self-nominate themselves by sending a CV to the organizers. During 2022 we expect to hold two seminar per month, and the events will take place in the last two Fridays of each month, from 10:45 AM-12:00 PM Eastern Standard Time (EST):
This event's talks:
Prediction of vapor-liquid equilibria of modern three- and four-site models of water
Prof. Jeffrey Potoff (Wayne State University)
Abstract: Water is perhaps the most studied molecule by molecular simulations, and given its importance, as well as the limitations of existing force fields, new water models are continually proposed. In this talk, I present new data for the vapor-liquid coexistence curves, vapor pressures, heats of vaporization and critical parameters for the OPC, OPC3, and GOPAL force fields. Additional comparisons are made to literature data for TIP4P-2005 and the exp-6 force field of Errington and Panagiotopoulos. Relationships between the target data used for parameter optimization and the performance of the force fields for VLE calculations is discussed. Additionally, I highlight some of the challenges present in achieving high quality sampling of phase space when simulating some water models at temperatures below 290 K, and present a few solutions, such as the use of multi-particle moves, more frequent volume exchanges, advanced configurational-bias methods, such as Molecular Exchange Monte Carlo (MEMC), and hybrid Monte Carlo/molecular dynamics methods.
Speaker Bio: Jeffrey Potoff is a Department Chair and Professor of Chemical Engineering and Materials Science at Wayne State University. He received his BS in ChE from MSU (1994), MS and PhD in ChE from Cornell (1997, 1999) advised by Thanos Panagiotopoulos, followed by post-doctoral work with the Siepmann group at the University of Minnesota (1999-2000). Potoff’s group develops molecular mechanics force fields for VLE prediction, Monte Carlo sampling algorithms and the high performance Monte Carlo software GOMC and hybrid MC/MD software py-MCMD; both of which are available from https://github.com/GOMC-WSU.
Predicting charge transfer rates: Marcus is good, but can we do better?
Dr. Subhajyoti Chaudhuri (Northwestern University)
Abstract: Due to its simple analytical form, Marcus Theory has been widely used to calculate electron transfer (ET) rates in a wide range of systems. In this talk, I first discuss how electronic structure theory can be used to calculate Marcus ET rates; followed by some of the shortcomings/ limitations of the theory, and how to move towards more accurate modeling of charge transfer processes by modifying Marcus theory and combining it with electronic structure and stochastic methods.
Speaker Bio: Subhajyoti ‘Subha’ Chaudhuri obtained his PhD from Yale University working with Prof. Victor Batista on developing electronic structure theory-based methods to model charge transfer processes in weakly coupled systems. At present, he is a postdoctoral scholar in the group of Prof. George Schatz at Northwestern University. His research involves utilizing charge, spin, and energy transfer processes for applications ranging from designing reactions for critical metals separation to designing materials for quantum transduction.