title: Contribution of hydrogen bonding to charge-transfer induced surface-enhanced Raman scattering of an intermolecular system comprising p-aminothiophenol and benzoic acid.
abstract: We investigated the influence of hydrogen bonds (H-bonds) on the intermolecular interactions of a system comprising p-aminothiophenol (PATP) and benzoic acid (BA) using surface-enhanced Raman scattering (SERS) for the first time. In this system, H-bonds form through intermolecular interactions between the -NH2 and -COOH groups and promote the charge-transfer (CT) transition from the Ag substrate to the adsorbed PATP molecules. Accordingly, the intensities of the non-totally symmetric vibrations (the b2-type bands) of PATP are influenced through the Herzberg-Teller contribution. This is clearly a BA concentration-dependent phenomenon. This behaviour can be attributed to an increase in the degree of conjugation of the system, which facilitates the CT process in the system with H-bonds. Furthermore, temperature-dependent SERS experiments and their two-dimensional (2D) correlation analysis confirmed that the formation of H-bonds facilitated the CT transition between the adsorbed molecules and substrate. The degree of CT was reduced by H-bond breakage that occurred with increasing temperature. An additional SERS experiment involving substituted BA molecules yielded similar conclusions.
authors.affiliation: State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, P. R. China. zhaob@mail.jlu.edu.cn.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Ji
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yu
authors.forename: Ran
authors.initials: R
authors.lastname: Li
authors.forename: Xu
authors.initials: X
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.forename: Weidong
authors.initials: W
authors.lastname: Ruan
authors.forename: Bing
authors.initials: B
authors.lastname: Zhao
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ozaki