A theoretical chemistry approach to vibro-polaritonic chemistry with application to infrared spectroscopy and reaction kinetics

Abstract

The emerging interdisciplinary research field of vibro-polaritonic chemistry exploits the concept of vibrational strong coupling (VSC) to shape chemical reactivity and molecular properties. Vibro-polaritonic chemistry employs optical Fabry–Pérot cavities as a novel light source, which provide access to VSC between confined infrared (IR) radiation modes and molecular (ro)vibrational degrees of freedom. VSC induces the formation of light–matter hybrid states known as vibrational polaritons, which are experimentally characterized by a paradigmatic doublet signature in linear IR spectra. Mechanistically even more intriguing is the experimentally reported observation of VSC-modified ground state chemistry. From a conceptual perspective, vibro-polaritonic chemistry differs from traditional laser-based light–matter interaction scenarios: While the latter commonly rely on a semiclassical approach subject to a classical description of the electromagnetic field, in vibro-polaritonic chemistry the entire light–matter hybrid system is described quantum mechanically. This chapter provides a contemporary overview of vibro-polaritonic chemistry from the perspective of a theoretical chemist. Theoretical concepts extending the common quantum chemical perspective towards molecular interactions with quantized cavity radiation fields are presented in an introductory fashion. Applications to linear IR spectroscopy and reaction kinetics in the VSC regime are illustratively discussed for selected model problems.