In this project supported by the Experimental Physical Chemistry Program of the Chemistry Division, Robert Curl of Rice University will investigate the high-resolution infrared spectra of reactive free radicals using infrared kinetic spectroscopy. The two species of particular interest are propargylene (HCCCH) and hydroxymethyl (CH2OH). New methods for high resolution infrared spectroscopy using difference frequency mixing of two laser sources will also be developed and applied. A sensitive high-speed infrared detector based on sum frequency generation will also be developed. Several sources of laser radiation in rugged, portable form currently exist in the visible and near infrared spectral regions. The techniques and detectors being developed under this research program will extend the accessible spectral wavelengths into infrared, which is important as a `fingerprint` region where different chemicals can be uniquely identified. Such radiation sources will be useful in many applications, from species monitoring in refinery and petrochemical industries to monitoring of the environment. The latter application is particularly unique because it allows high sensitivity detection without requiring coolants and is not affected by large amounts of environmental infrared background radiation.
