报告题目：Signatures of Chirality Recognition, Transfer, and Amplification: Chiral Molecules Under Resonance and at Interfaces
主讲人：徐云洁教授 Yunjie Xu，Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada, T6G 2G2
Yunjie Xu is a full professor and Tier I (Senior) Canada Research Chair in Chirality and Chirality Recognition in the Chemistry Department at the University of Alberta. Her research focuses characterizing chirality and chiral recognition/transfer/amplification/ at the molecular level. Her group not only applies vibrational circular dichroism, Raman optical activity, and rotational spectroscopy but also develops new IR-mass spectrometry techniques to study chirality related processes in the gas phase, in solution, and at the liquid-liquid interfaces. She has published 182 refereed articles in leading scientific journals including Science, Angew. Chem. Int. Ed., J. Am. Chem. Soc., J. Phys. Chem. Lett. and Phys. Rev. Lett.
She has received many awards and honors and some recent ones are 2019 Gerhard Herzberg Award from Canadian Society for Analytical Sciences and Spectroscopy, 2020 Philip J. Stephens Award from International Conference Series on Vibrational Optical Activity, 2022 Ioannes Marcus Marci Medal for outstanding achievements in high resolution molecular spectroscopy, and the exceptional (highest) ranking in the 2023 NSERC Discovery Grant Competition. She was elected to the Fellowship of the Royal Society of Canada, Academy of Science in 2018.
A molecule is chiral if its mirror image cannot be superimposed onto itself. Chirality serves an essential function in life. Our research program centers on understanding mechanisms of chirality recognition, transfer, amplification at the molecular level. To achieve this goal, we apply and develop new spectroscopic tools to characterize structural and dynamical properties of chiral molecules and non-covalent interactions among them. We examine chirality-related properties of systems in different size regimes, from small chiral molecules to atomically precise metal clusters and to metal nanoparticles, under varying conditions, from the gas phase to cold rare gas matrices, solution, and liquid-liquid interfaces. We emphasize the connection among different size regimes and conditions to extract new physical insights into these chirality events.
While carrying out Raman optical activity (ROA) measurements of several transition metal complexes under resonance, we detected very strong chiral Raman signals of achiral solvents. Our search for possible mechanisms let us to the discovery of a new form of chiral Raman spectroscopy called eCP-Raman. eCP-Raman combines two spectroscopies into one: electronic circular dichroism and circularly polarized Raman (CP-Raman). Our results also indicate that many previous resonance ROA measurements may be contaminated with eCP-Raman contributions. I Efforts to extract/predict (near)resonance ROA experimental/theoretically will be described. Lastly, I will discuss a recent chirality recognition study at an organic and water interface using interfacial tension measurements and MD simulations.