Chemical Physics

SRI's research in chemical physics focuses on the electronic spectroscopy and collision dynamics of small molecules important in the atmosphere and combustion, such as OH, NO and NO₂. Our team's experiments use laser-induced fluorescence, typically in low-pressure flow cells, but also in flames. Through both theory and experiment we have established accurate transition probabilities for OH and CS, plus several band systems in NO and CH.

SRI studies of collisional processes in small molecules include novel two-laser pump probe studies of quantum-state-specific rotational energy transfer in the ground electronic state of the OH radical and an excited electronic state of NO. These OH results have been compared with quantum scattering calculations performed on a high quality potential energy surface. Quenching and vibrational energy transfer results as a function of temperature between 200 and 1500K have been used in quantitative determinations of OH and NO in the troposphere and stratosphere, and CH in low pressure and atmospheric pressure natural gas flames.

The results from work in chemical physics research area over the last 20 years are in use worldwide. Due to the research's fundamental nature and SRI's wide distribution of our results, funding has largely been provided by government or industry consortia, including NASA, NSF, and GRI.

Visit the Laboratory - Molecular Physics Laboratory

Technical Contact:
David R. Crosley
(650) 859-2395
david.crosley@sri.com