ROTATIONAL SPECTRUM OF THE ISOPRENE-WATER COMPLEX

Measuring the structure of molecular dimers is a stepping stone in the study of chemical interactions. These structures are normally highly sensitive to the two-body potential and therefore form a basis for interpreting structure, dynamics, and reactions in more complex systems. Studies of strong and weak hydrogen bonded clusters have provided important insight into the nature of these interactions. The structures of numerous dimers have been determined, however many complexes, especially those involving weakly polar species such as isoprene, have not been measured. Isoprene(C$_5$H$_8$), the simplest terpene, is the building block for terpenes and terpenoids, many of which are volatile compounds released by trees and shrubs. Isoprene accounts for 50\% of biogenic non-methane hydrocarbon emission, and is therefore a major contributor to aerosol production. Furthermore, the composition of isoprene-derived aerosols varies significantly with relative humidity. The study of the structure of heterogeneous isoprene clusters is therefore of considerable interest for furthering our understanding of the interactions that drive isoprene chemistry. Towards this end, we will present the pure rotational spectrum of the isoprene-water complex recorded with a chirped-pulse Fourier transform microwave spectrometer, and discuss the structure of the complex