Advances in Vibrational Stark Shift Spectroscopy for Measuring Interfacial Electric Fields
Sohini Sarkar, Cindy Tseng, Anwesha Maitra, Matthew J. Voegtle, Jahan M. Dawlaty
Abstract
Measuring, modeling, and engineering electric fields on the molecular scale is essential for controlling a number of chemical and physical phenomena. A major challenge towards this goal is quantifying electric fields on the microscopic scales. Towards that goal, we will discuss recent advances in Stark shift spectroscopy, with emphasis on its applications in deciphering interfacial electric fields and related phenomena. This chapter has two parts. First, we will describe the foundations, limitations, and potentials of using vibrational Stark probes, with focus on benzonitriles, for measuring electrostatic fields. In the second part we will describe recent applications of benzonitrile Stark shift probes for understanding various interfacial phenomena, including dipolar solvation, fields at electrode-electrolyte junctions, electrostatics and packing competition at the ionic liquids-metal junctions, interfacial hydration in the presence of ionic liquids, and the interplay between a proton-coupled electron transfer reaction and the electrostatics of the interface. We highlight both future prospects and limitations of using such probes for better understanding of chemical microenvironments.