Can One Measure Resonance Raman Optical Activity?. (27th August 2021)

• Record Type: Journal Article
• Authors: Li, Guojie; Alshalalfeh, Mutasem; Yang, Yanqing; Cheeseman, James R.; Bouř, Petr; Xu, Yunjie
• Is Part Of: Angewandte Chemie. Volume 133:Number 40(2021)
• Page Start: 22175
• Page End: 22180
• Publication Date: 2021-08-27
• Subjects: chiral Raman spectroscopy -- circularly polarized Raman -- electronic circular dichroism -- finite-lifetime approach -- resonance Raman optical activity; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202109345
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Resonance Raman optical activity (RROA) is commonly measured as the difference in intensity of Raman scattered right and left circularly polarized light, IR −IL, when a randomly polarized light is in resonance with a chiral molecule. Strong and sometimes mono‐signate experimental RROA spectra of several chiral solutes were reported previously, although their signs and relative intensities could not be reproduced theoretically. By examining multiple light‐matter interaction events which can occur simultaneously under resonance, we show that a new form of chiral Raman spectroscopy, eCP‐Raman, a combination of electronic circular dichroism and circularly polarized Raman, prevails. By incorporating the finite‐lifetime approach for resonance, the experimental patterns of the model chiral solutes are captured theoretically by eCP‐Raman, without any RROA contribution. The results open opportunity for applications of eCP‐Raman spectroscopy and for extracting true RROA experimentally. Abstract : Measured resonance Raman optical activity (RROA) often did not agree with theoretical predictions. We uncover a new form of chiral Raman spectroscopy, eCP‐Raman, that explains some of these inconsistencies. This combination of electronic circular dichroism and circularly polarized Raman has also immense potential as a sensitive technique for applications in chemistry or biology.