OSE Seminar by Dr. Kirk on Donor-Acceptor Systems Provide Insight into Charge Separation, Charge Transport, and Excited State Processes

Departmental News

OSA Capitol Hill Visit

Posted: February 23, 2022

Date: Thursday, February 24, 2022

Time:  11 AM - 12 PM

Location:  at PAIS, Rm. 1100

Abstract:

Excited state interactions in spin-containing Donor-Acceptor and Donor-Bridge-Acceptor systems are important for understanding the impact of electronic coupling (Hab) on molecular conductance and how magnetic exchange interactions affect excited state processes. Our efforts have focused on determining excited state contributions to molecular bridge mediated electronic coupling, understanding how open-shell excited state singlet configurations promote long-range electron correlation, correlating magnetic exchange with molecular conductance, and developing new platforms for spin control of excited state dynamics in photoexcited donor-acceptor molecules. Using novel Donor-Bridge-Acceptor biradical and related complexes, we have been able to test recent theoretical hypotheses in molecular electronics as they relate to coherent superexchange in electron transfer/transport conduits and the control of quantum interference effects. Radical elaborated transition metal complexes represent ideal platforms for exploring the relationship between photoinduced charge separation and long-range spin correlation, impacting the solar energy, organic lighting, and molecular spintronics fields. These systems are also relevant to the emerging molecular quantum information science (QIS) field, allowing for the optical generation and manipulation of spin qubits. Here we will show how a combined spectroscopic and magentic approach, augmented by detailed bonding calculations, has provided keen insight into the electronic structure of these novel radical containing complexes in order to further our understanding of molecular electronic systems at the nanoscale.

Biography:

Martin L. Kirk is Distinguished University Professor of Chemistry and Chemical Biology at The University of New Mexico. His research program focuses on (1) spectroscopic, synthetic, biochemical, and computational studies of pyranopterin molybdenum enzymes and models, (2) detailed magnetic, spectroscopic, and theoretical studies of spin containing molecular systems in the context of molecular electronics, and (3) optical generation of multiple spin qubits for quantum information science (QIS) applications. He has been a Research Fellow (7/03-1/04) at the Glenn T. Seaborg Institute at Los Alamos National Laboratories during a sabbatical leave and was Humphrey Symposium Lecturer at the University of Vermont, PROTRAIN Lecturer at Braunschweig Technical University (Germany), and the Highlands in Chemistry Lecturer at Virginia Tech. He was a National Science Foundation Postdoctoral Fellow (1990-1993, Stanford University) with E. I. Solomon, completed his Ph.D. in 1990 at The University of North Carolina at Chapel Hill with W. E. Hatfield, and obtained his B.S. in 1985 at West Virginia University performing undergraduate research with Naresh Dalal. He was guest Editor (with Prof. D. A. Shultz) for Molecular Spintronics: a web themed issue in Chemical Communications and an Editor of Molybdenum and Tungsten Enzymes; a three volume Metallobiology Series sponsored by the Royal Society of Chemistry. Prof. Kirk has served on the Editorial Board of Inorganic Chemistry, was a prior ACS Inorganic Division Chair of the Bioinorganic Subdivision, and a Chair of the Gordon Research Conference on Molybdenum and Tungsten Enzymes. He was Adjunct Professor of Chemistry at New Mexico Institute of Mining and Technology and is currently a member of UNM’s Center for High Technology Materials and the Center for Quantum Information and Control.