DEPARTMENT OF CHEMISTRY

Research Statement

Our research goal is to establish relationships of energetics, dynamics and structures in photochemical and photophysical processes on different temporal and spatial scales in a variety of systems from small molecules to biomacromolecules. We are interested in studying light-matter interactions in terms of interplays of electrons and nuclei of molecular, nanostructured, supramolecular systems as well as solid materials related to light energy conversion, catalysis, optoelectronic devices and enzymatic processes. Using a variety of experimental techniques, such as ultrafast optical and X-ray spectroscopy/scattering, as well as theoretical calculations through collaborations, we seek fundamental understandings of light-matter interactions and finding solutions for reduction energy losses, directional charge transfer and accumulation for optimized photochemical reactions. The results from our research provide feedback/guidance to materials design and synthesis.

Selected Publications

Revealing Parallel Inter- and Intra-Ligand Charge Transfer Dynamics in [Ru(L)2(dppz)]2+ Molecular Lightswitch with N K-Edge X-Ray Absorption Spectroscopy, Elizabeth S. Ryland, Xinzheng Yang, Douglas Garratt, Wade C. Henke, Abdullah Kahraman, Maxwell Taub, Michael Sachs, Elisa Biasin, Christina Y. Hampton, David J. Hoffman, Giacomo Coslovich, Kristjan Kunnus, Georgi L. Dakovski, Michael W. Mara, Lin X. Chen, Karen L. Mulfort, Xiaosong Li, Amy A. Cordones, Angew. Chem. Intl. Ed. 64, e202509496 (2025).

Early Folding Dynamics of i-Motif DNA Revealed by pH-Jump Time-Resolved X-ray Solution Scattering, Arnold M. Chan, Sasha B. Ebrahimi, Devleena Samanta, Denis Leshchev, Adam K. Nijhawan, Darren J. Hsu, Madeline B. Ho, Namrata Ramani, Irina Kosheleva, Robert Henning, Chad A. Mirkin, Kevin L. Kohlstedt, Lin X. Chen, J. Am. Chem. Soc. 146, 33743-33752 (2024) DOI 10.1021/jacs.4c11768

Spin-vibronic coherence drives intersystem crossing, Shahnawaz Rafiq, Nicholas P. Weingartz1, Sarah Kromer, Felix N. Castellano, Lin X. Chen, Nature  DOI: 10.1038/s41586-023-06233-y  (2023).

Revealing Excited State Trajectories on Potential Energy Surfaces with Atomic Resolution in Real Time, Denis Leshchev, Andrew J. S. Valentine, Pyosang Kim, Arnab Chakraborty, Elisa Biasin, Kristoffer Haldrup, Darren J. Hsu, Matthew S. Kirschner, Dolev Rimmerman, Matthieu Chollet, J. Michael Glownia, Tim Van Driel, Felix Castellano, Xiaosong Li, Lin X. Chen, Angew. Chem. Intl. Ed. https://doi.org/10.1002/anie.202304615   (2023).

Large Exciton Diffusion Coefficients in Two Dimensional Covalent Organic Frameworks with Different Domain Sizes Revealed by Ultrafast Exciton Dynamics, Nathan C. Flanders, Matthew S. Kirschner, Pyosang Kim, Thomas J. Fauvell, Austin M. Evans, Waleed Helweh, Austin P. Spencer, Richard D. Schaller, William R. Dichtel, Lin X. Chen, J. Am. Chem. Soc. https://doi.org/10.1021/jacs.0c05404 (2020).

In Situ Grazing-Incidence Wide-Angle Scattering Reveals Mechanisms for Phase Distribution and Disorientation in 2D Halide Perovskite Films. Hoffman, J. M.;  Strzalka, J.;  Flanders, N. C.;  Hadar, I.;  Cuthriell, S. A.;  Zhang, Q.;  Schaller, R. D.;  Dichtel, W. R.;  Chen, L. X.; Kanatzidis, M. G., Advanced Materials 2002812 DOI: 10.1002/adma.202002812 (2020).

X-ray snapshots reveal conformational influence on active site ligation during metalloprotein folding, Darren J. Hsu, Denis Leshchev, Dolev Rimmerman, Jiyun Hong,   Matthew S. Kelley, Irina Koshelev, Xiaoyi Zhang, Lin X. Chen, Chem. Sci. 10, 9788–9800 (2019).

Photoinduced, reversible phase transitions in all-inorganic perovskite nanocrystals, Kirschner, M. S.; Diroll, B. T.; Guo, P.; Haryey, S. M.; Helweh, W.; Flanders, N. C.; Brumberg, A.; Watkins, N. E.; Leonard, A. A.; Evans, A. M.; Wasielewski, M. R.; Dichtel, W. R.; Zhang, X.; Chen, L. X.; Schaller, R. D. Nature Communications 10, 504 (2019). 

Coherent Vibrational Wavepacket Dynamics in Platinum(II) Dimers and Their Implications, Pyosang Kim, Matthew S. J. Kelley, Arnab Chakraborty, George C. Schatz, Felix N. Castellano, Lin X. Chen, J. Phys. Chem. C (invited for Kamat Special Issue) 122, 14195–14204 (2018).

Probing Cytochrome c Folding Transitions upon Photo-triggered Environmental Perturbations Using Time-Resolved X-Ray Scattering, Dolev Rimmerman, Denis Leshchev, Darren J. Hsu, Jiyun Hong, Baxter Abraham, Robert Henning, Irina Kosheleva, Lin X. Chen, J. Phys. Chem. B, 122, 5218−5224 (2018).

Using coherence to enhance function in chemical and biophysical systems, Scholes, G. D.; Fleming, G. R.; Chen, L. X.; Aspuru-Guzik, A.; Buchleitner, A.; Coker, D. F.; Engel, G. S.; van Grondelle, R.; Ishizaki, A.; Jonas, D. M.; Lundeen, J. S.; McCusker, J. K.; Mukamel, S.; Ogilvie, J. P.; Olaya-Castro, A.; Ratner, M. A.; Spano, F. C.; Whaley, K. B.; Zhu, X. Nature 543, 647-656 (2017).

Selected Honors/Awards

• ACS E. Bright Wilson Award, 2026
• Mildred Dresselhaus Guest Professorship, University of Hamburg, 2024
• Baker Lecturer, Cornell University, 2024 
• Fellow of American Crystallography Association, 2022
• Fellow of Royal Society of Chemistry, 2021
• Argonne Distinguished Fellow, 2020
• Senior Award of Experimental Physical Chemistry, ACS, 2020
• American Association for the Advancement of Science (AAAS) Fellow, 2012
• Distinguished Performance Award at Argonne, 2002