The Beck Laboratory

Professor Warren F. Beck

Current Research

Carotenoid Photophysics

National Science Foundation, Chemistry of Life Processes program. Collaborative Research: Combining Theory and Experiment to Understand Carotenoid Photophysics in Photosynthetic Light-Harvesting." Jose Gascon, University of Connecticut, award CHE-1904700; Warren Beck, Michigan State University, award CHE-1904655. 9/1/19–8/31/22.

In collaboration with Professor José Gascón (Department of Chemistry, UConn), we are studying the potential energy surfaces and binding sites for the active carotenoids involved in photosynthetic light harvesting and photoprotection mechanisms.

The experimental parts of this collaborative project are intended to determine how the structure of a carotenoid evolves after optical preparation of the S2 state by absorption of a mid-visible photon. The approach in this part of the work will employ a combination of fluorescence and broadband two-dimensional electronic spectroscopy (2DES) spectroscopy with anisotropy detection, which directly monitors the time evolution of the orientation of the transition dipole moment in the S2 state.

Model potential energy curves for carotenoids with respect to the motions that follow optical excitation to the second excited singlet state
Model potential energy curves for carotenoids with respect to the motions that follow optical excitation to the second excited singlet state


Light Harvesting Proteins and Photoprotection

Department of Energy, Basic Energy Sciences, Photosynthetic Systems program, second renewal of grant award DE-SC0010847. Energy transfer and radiationless decay in light-harvesting proteins. $579,921, 9/1/19–8/31/22.

This project seeks to determine the photophysical and structural mechanisms that mediate excitation energy transfer and photoprotection in photosynthetic light harvesting systems.

In collaboration with Professor Cheryl Kerfeld (MSU–DOE Plant Research Laboratory and LBNL), we are currently investigating the mechanisms that allow the orange carotenoid protein (OCP) to mediate nonphotochemical quenching mechanisms by binding to the core of the cyanobacterial phycobilisome. We are interested in the photochemical details that convert OCP to its active, orange form, and we are going to determine the nature of the quenching reaction that OCP mediates in the core of the phycobilisome. The latter involves broadband 2DES studies of excitation transfer processes in intact phycobilisomes.

Structure of OCP and detail of the canthaxanthin binding site.
Structure of OCP and detail of the canthaxanthin binding site.


Semiconductor Quantum Dots

Department of Energy, Basic Energy Sciences, Solar Photochemistry program. Light-harvesting in semiconductor quantum dots. Award DE-SC0021197. PI: Warren Beck, Michigan State University; co-PIs Ben Levine, Stony Brook University, and Gregory Van Patten, Middle Tennessee State University.

In collaboration with Professors Greg Van Patten and Mengliang Zhang (Department of Chemistry, MTSU) and Professor Ben Levine (Department of Chemistry, SBU), we are investigating the dynamics hot-carrier cooling processes in semiconductor quantum dots. A goal of this work is to probe with broadband 2DES the involvement of the vibrational motions of the organic surface-capping ligands in CdSe quantum dots.

Organic surface-capping ligands for CdSe quantum dots
Organic surface-capping ligands for CdSe quantum dots