Henry L. Pierce Laboratory Seminar with Prof. James De Yoreo
Wednesday, December 11, 2019 at 4:00pm to 5:00pm
They Call It Free Energy, So Hey, Why Pay?
Hierarchical organization is a fundamental principle underlying the high level of function achieved by materials produced in living systems. Current efforts to create functional materials through purely synthetic routes often emulate this pervasive feature of Nature. Observations over the past decade have shown that these complex structural outcomes are accompanied by a rich set of hierarchical assembly pathways involving building blocks far more complex than simple ions, atoms or molecules. Yet the basic physical model for the development of order during the earliest stages of materials formation first proposed by J.W. Gibbs in the 1800s appears to be inherently at odds with the achievement of hierarchical outcomes, predicting instead simple compact structures through simple assembly pathways. In the case of self-assembled macromolecular architectures, which exhibit a range of hierarchical motifs from particles to ribbons to sheets, these pathways become yet more complex due to the vast landscape of structural states that an individual macromolecule can explore. Despite these complexities, a holistic framework for understanding hierarchical pathways that is rooted in classical concepts emerges when the coupled effects of perturbations in free energy landscapes and the impact of dynamical factors are considered. Here I describe that framework and use in situ TEM and atomically resolved in situ AFM studies on inorganic, organic, and macromolecular systems to illustrate the evolution in assembly pathways as these perturbations and dynamical factors come into play. The results provide a common basis for understanding the development of order in diverse systems.
Jim De Yoreo is a Battelle Fellow and Chief Scientist for Materials Science in the Physical and Computational Sciences Directorate at Pacific Northwest National Laboratory (PNNL), an Affiliate Professor of Materials Science and Engineering and of Chemistry at the University of Washington, and Co-Director of the Northwest Institute for Materials Physics, Chemistry and Technology (NW IMPACT). He received his PhD in Physics from Cornell University in 1985. Following post-doctoral work at the University of Maine and at Princeton University, he became a member of the technical staff at Lawrence Livermore National Laboratory in 1989, where he held numerous positions. He joined Lawrence Berkeley National Laboratory in 2007 where he served as Deputy and then Interim Director of the Molecular Foundry before moving to PNNL in 2012. De Yoreo’s research has spanned a range of materials-related disciplines, focusing recently on interactions, assembly, and crystallization in inorganic, biomolecular and biomineral systems. De Yoreo has authored, co-authored, or edited over 250 publications and patents. He is a recipient of the David Turnbull Lectureship of the Materials Research Society (MRS), the Laudise Prize of the International Organization for Crystal Growth (IOCG) and the Crystal Growth Award of the American Association for Crystal Growth (AACG). He served as President of the MRS and he is a Fellow of the American Physical Society and the MRS, and a member of the Washington State Academy of Sciences and the IOCG and AACG Executive Committees.