MEETS (Materials, Energy, EnvironmenT Seminars)

Dr. Jason Anspach joined Phenomenex in 2005 as a Senior Research scientist in Research and Development.  From 2005 until 2019 he held several roles within the R&D department focusing on new column technology with an emphasis on advancements in column packing and hardware.  In 2019 Jason joined the product management team where he led the management team handling the portfolio of products servicing the industries of small molecule pharmaceuticals, clinical diagnostics, environmental, as well as chemicals and fuels. 

In December of 2024 Jason returned to the R&D team as the Director of Research and Open Innovation where his team focuses on collaborations with research and technology leaders in the separation sciences with the purpose of accelerating technological advancements, and the discovery of new technologies in the separations sciences space.

Dr. Anspach earned a Bachelor of Science in Chemistry from Binghamton University (State University of New York) and is a proud alumnus of our department, having completed his Ph.D. in Chemistry at the University at Buffalo in the Colón laboratory.

presented by: Leandro Wang Hantao, UNICAMP, Brazil

12:00 Noon in 684 Natural Sciences Complex, UB North Campus

The unifying theme in the Barnett group is the design of open space, an idea that we tackle at the molecular, macromolecular, and extended material levels. This talk will detail efforts at each of these three scales, demonstrating how a detailed understanding of voids and their dynamic natures can allow for discoveries of both applied and fundamental interest. The first part of the talk will cover synthetic molecular inorganic chemistry, focusing on the coordination chemistry of a new macrocycle-bearing ligand developed in our lab. By isolating a metal coordination site within permanent open space, we have succeeded in isolating high-valent first-row metal complexes that display highly unusual reactivity profiles. Additionally detailed will efforts using porous materials – both molecular and framework-based – that have resulted in breakthroughs relevant to separation science. This section will focus primarily on applications involving the capture and abatement of fluorinated “forever chemicals” that are of increasing environmental and health concern.

Topological band theory transformed our understanding of crystalline materials by classifying the connectivity and crossings of electronic energy levels. Despite many fundamental questions, extending these concepts to molecular systems has recently attracted significant interest. Reactions governed by orbital symmetry conservation are ideal candidates, as they classify pathways as symmetry-allowed or symmetry-forbidden depending on whether molecular orbitals cross along the reaction coordinate. However, the presence of strong electronic correlations in these reactions invalidate the framework underlying topological band theory, preventing direct generalization. Here, we introduce a formalism in terms of Green's functions to classify orbital symmetry controlled reactions even in the presence of strong electronic correlations. Focusing on prototypical 4π electrocyclizations, we show that symmetry-forbidden pathways are characterized by crossings of Green's function zeros, in stark contrast to the crossings of poles as predicted by molecular-orbital theory.  We introduce a topological invariant that identifies these symmetry protected crossings of both poles and zeros along a reaction coordinate  and outline generalizations of our approach to reactions without any conserved spatial symmetries along the reaction path. Our work lays the groundwork for systematic application of modern topological methods to chemical reactions and can be extended to reactions involving different spin states or excited states.