Revealing the difference of Stark tuning rate between interface and bulk by surface-enhanced infrared absorption spectroscopy

Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field. Here using surface-enhanced infrared absorption (SEIRA) spectroscopy, attenuated total reflection (ATR) spectroscopy and molecular dynamics (MD), we reveal the assembled C equivalent to N at gold nanofilm exhibits a reduced Stark tuning rate (STR) referring to the vibrational frequency shift in response to electric field comparing with the bulk which was regulated by the electron transfer between S and Au. These findings lead to a deeper understanding of the vibrational Stark effect at the interface and provide guidance for improving the interface electric field theory. (c) 2024 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.