2022 Volume 16 Issue 1 Pages A0122-
The interfacial chemical phenomenon plays an important role in modern chemistry and chemical engineering process. However, the detecting and microscopic understanding of the interfaces are still limited due to a lack of surface-specific techniques. Recent sum frequency generation (SFG) spectroscopy has been established as a powerful interface probe technique and provides valuable information at various interfaces, such as electrode/electrolyte and membranes. However, the observed SFG spectra are often hard to be interpreted and reliable theoretical support is strongly desirable. In this work, we have proposed a systematic method to generate non-empirical polarizable force fields and realized the simulation of SFG spectra of organic interfaces. The complicated SFG spectra are fully decomposed and the microscopic information of organic interfaces is extracted by the collaboration of SFG and molecular simulation. Furthermore, we discussed the effect of vibrational resonant components, such as quadrupole contribution and Fresnel factor dispersion, in the quantitative analysis of SFG spectra at organic interfaces. This work provides new aspects in the future study of complex organic interfaces through the SFG technique.