Knowledge Bank

The in situ photochemistry of dopant molecules isolated in solid parahydrogen (pH$2$) typically differs from analogous studies in rare gas crystals for two main reasons: (1) solid pH$2$ has a negligible cage effect so that photodissociation of a precursor molecule can lead efficiently to well-separated fragments, and (2) radical fragments can potentially react with the pH$2$ matrix. Our group is currently studying the 193 nm photochemistry of a number of precursor molecules isolated in solid pH$2$ via high-resolution FTIR spectroscopy in hopes of identifying trapped atomic species. Currently we are revisiting the photochemistry of NO in solid pH$2$ that has previously been investigated by Momose and co-workers.\textbf{29}, 740 (2003).} The 193 nm photodynamics of NO in rare gas matrices has also been extensively studied.\textbf{109}, 7784 (1998).} The studies by Momose showed that NO is photolabile at 193 nm and that the product N and O atoms react to form NH$3$ and H$2$O, respectively. Preliminary experiments in this laboratory show evidence for the production of the imidogen (NH) radical as well, and the most recent results and analysis will be presented.