Speaker:

Dr. Sapna Sarupria, Department of Chemistry, University of Minnesota

Abstract:

Heterogeneous ice nucleation refers to ice nucleation driven by the presence of a surface. This plays a critical role in atmospheric chemistry where the phase transitions in water (and hence, precipitation) depends on these particles. There are a wide variety of surfaces that can module ice nucleation – from organic crystals to mineral dust and biological molecules. It, however, remains unclear what makes some surfaces good ice nucleators and others poor nucleators. Whether there are some common signatures that define good ice nucleators or whether there are multiple pathways to achieve improved nucleation also remains an open question. In our work, we investigated these questions using detailed studies of ice nucleation on mineral surfaces and soft polymeric surfaces. We use molecular dynamics (MD) simulations to probe the molecular details of the process. The challenge in using MD for ice nucleation studies is the long simulation timescale requires to overcome the free energy barrier to form an ice nucleus. In many cases, this might not even be possible. Therefore, we have also developed advanced sampling methods that enable us to study ice nucleation in simulations.

Biography:

Dr. Sapna Sarupria is an associate professor in the department of Chemistry at the University of Minnesota, Twin Cities (UMN). Before joining UMN in Fall 2021, she was an associate professor in the department of Chemical and Biomolecular Engineering at Clemson University. She received her Master’s from Texas A & M University and her Ph.D. from Rensselaer Polytechnic Institute. She was a postdoctoral researcher in Princeton University. Her research focuses on using molecular simulations to tease out the underlying phenomena governing material behavior. Her passion for computational molecular science comes from her love to answer the question “why” and her love for programming. Sarupria research group is involved in a broad range of projects – ice and hydrate nucleation, development of simulation methods to study rare events, modeling of water purification membranes, and modeling biomolecular assemblies. She received the NSF CAREER award, ACS COMP Outstanding Junior Faculty Award and Clemson’s Board of Trustees Award of Excellence. Along with research, Sarupria is passionate about enhancing diversity, inclusion, and equity in academia and more broadly in the society. She has actively mentored students and faculty from various backgrounds and enjoys building bridges across different cultures. She is the past-Chair of the Computational and Molecular Science and Engineering Forum (CoMSEF) in AIChE and the incoming chair of the Theory subdivision of Physical Chemistry division at ACS. She is the co-founder of the NSF-funded Institute of Computational Molecular Science Education (I-CoMSE), which is focused on creating a sustainable ecosystem for training the next generation in molecular simulation cyberinfrastructure while enhancing education accessibility and equity. She is the associate editor for LiveCoMS -- Living Journal of Computational Molecular Simulation, a modern and innovative peer-reviewed home for manuscripts which share best practices in molecular modeling and simulation.