Solvent effect on the initial structural dynamics of benzaldehyde in the S3(ππ*) state—Resonance Raman spectroscopic study. (7th February 2019)

• Record Type: Journal Article
• Authors: Chen, Jia; Jiang, Xuelian; Xue, Jiadan; Wang, Huigang; Zheng, Xuming
• Is Part Of: Journal of Raman spectroscopy. Volume 50:Number 5(2019)
• Page Start: 684
• Page End: 695
• Publication Date: 2019-02-07
• Subjects: benzaldehyde -- CASSCF computation -- resonance Raman -- structural dynamics -- time‐dependent wave‐packet theory; Raman spectroscopy -- Periodicals; 535.846
• DOI: 10.1002/jrs.5573
• Languages: English
• ISSNs: 0377-0486

Abstract

Abstract: The excited‐state structural dynamics of benzaldehyde (BA) after population to the S3 (πH‐1 πL *) light‐absorbing state were studied using resonance Raman spectroscopy and complete active space self‐consistent field (CASSCF) calculations. The C‐band absorption cross section and the corresponding absolute resonance Raman cross sections in cyclohexane and methanol were simulated using the time‐dependent wave‐packets formalism, respectively. The results indicate that the major structural dynamics of BA and the homogeneous broadening of the absorption spectrum in cyclohexane are similar to those of BA in methanol or acetophenone (AP) in cyclohexane, whereas the inhomogeneous broadening of BA in cyclohexane is significantly different from that in methanol. It is proposed that the initial decay pathway of BA upon the C‐band absorption is mostly towards S3 S2 and partly to S3, min . The roles of hydrogen bonding and polar–polar interaction in the spectral broadenings are discussed. Abstract : The excited‐state structural dynamics of benzaldehyde (BA) after population to the S3 (πH‐1 πL *) light‐absorbing state were studied using resonance Raman spectroscopy and CASSCF calculations. Simulation results of the C‐band absorption cross section and the corresponding absolute resonance Raman cross sections with time‐dependent wave‐packets formalism presented insight into the curve‐crossing dynamics between S3 (ππ*) and the low‐lying states and the solvent effect.