Spin and Spin Polarization Effects in Electron and Energy Transfer Processes

Wednesday, March 27, 2013

1:15pm | 125 Hudson Hall

Presenter

James McCusker , Professor, Department of Chemistry

Electron spin is a fundamental property of Nature. Although many of the more common physical observables linked to spin are well documented (e.g. magnetism, spin-allowed v. spin-forbidden optical transitions), the degree to which spin and spin polarization permeates the chemistry of molecular systems is not as clear. This notion, namely the effect of spin and spin polarization on the physical and chemical properties of molecules, constitutes the conceptual underpinning of our research effort. Specifically, we are pursuing the design and development of chemical systems that will allow us to determine whether there exists a cause-and-effect relationship between the physical and/or photophysical properties of molecules and their innate spin properties, and if so, to what extent we can exploit this connection in order to manipulate the chemical reactivity of molecular systems. Several projects ongoing in the group specific to our interest in energy and electron transfer processes will be described, including proof-of-principle results for manipulating dipolar (i.e., Förster) energy transfer in a covalently-linked donor-acceptor assembly,1 as well as efforts currently underway to extend these concepts to molecular wires where zero-field spin polarization could be used to control electron flow.

Jim McCusker was born in New Haven, Connecticut in 1965. He obtained a combined B.S./M.S. degree from Bucknell University in 1987 working with Charles A. Root on oxovanadium chemistry. In 1992, McCusker received his Ph.D. from the University of Illinois at Urbana-Champaign with David N. Hendrickson studying the magnetic properties of polynuclear Mn and Fe clusters in addition to the spin-crossover dynamics of Fe(II) complexes. Following a two-year NIH post-doctoral fellowship with Professor Thomas J. Meyer at the University of North Carolina at Chapel Hill, McCusker began his independent career as an Assistant Professor at the University of California at Berkeley in 1994 focusing on the ultrafast excited-state properties of transition metal complexes; the initial paper out of his group was the first to identify the sub-100 fs dynamics associated with intersystem crossing in [Ru(bpy)3]2+. In January 2001, McCusker moved his research group to Michigan State University where he is currently Professor of Chemistry and Associate Chair for Research. His research continues to focus on the ultrafast dynamics of transition metal complexes – primarily those of the first transition series and their applications to solar energy conversion strategies – as well as the synthesis and characterization of transition metal-based assemblies for examining the effect of spin and zero-field spin polarization on electron and energy transfer processes.