Collaborative Research: Spectroscopy and Chemistry of Open-Shell Atoms in Solid Hydrogen Matrices

University Of Tennessee Knoxville, Knoxville TN

Investigators

Abstract

Professors David Anderson of the University of Wyoming and Robert Hinde of the University of Tennessee are supported by the Experimental Physical Chemistry Division for a collaborative investigation of the infrared (IR) spectroscopy and chemistry of cryogenic molecular hydrogen solids containing open-shell atoms as substitutional impurities. Through a combination of experiment (Anderson) and first principles simulations (Hinde) the project goal is to use the IR spectroscopy to quantify how the presence of the hydrogen ?solvent? perturbs the electronic structure of the open-shell atom. Most chemistry occurs in the presence of a solvent and these fundamental studies are aimed at understanding how solvent effects are manifested in simple atomic radical reactions with molecular hydrogen. This will be accomplished by first developing a theoretical framework for understanding the solvent-induced perturbation of the electronic structure of chlorine atoms (Cl) trapped in solid hydrogen. The knowledge gained in these halogen atom studies will then be applied to oxygen atom (O) doped solid hydrogen to study solvent perturbations of the prototypical combustion reaction of O-atoms with molecular hydrogen. The goal of this research is to develop the spectroscopic analysis such that solid hydrogen doped with atomic radicals can be used as a new reaction medium to study the details of low temperature chemistry in a condensed phase. Frozen molecular hydrogen is a unique crystalline solid that is distinguished as a quantum solid due to pronounced quantum mechanical effects of the hydrogen molecule at the low temperatures at which hydrogen freezes (T<13.8 K). These studies of chemical reactions in a quantum solid will have direct impact on our understanding of quantum mechanical effects in low temperature chemical reactions, the ability to use light to control chemical reaction pathways, and potentially provide transformative insight into both high gravimetric storage and clean production of molecular hydrogen. This research will also provide a rich vehicle for undergraduate and graduate research experience and training.