Waves or oscillations are common in gaseous plasmas. This work, supported by the Analytical and Surface Chemistry Program of the Chemistry Division, seeks to use the dependence of such oscillations on the chemical makeup of the plasma to detect assorted chemical species and to quantify them. Both the oscillation frequency and amplitude are related to the amount of analyte present. The sensitivity of this dependence is dependent on species structure. Plasmas are generally regarded as tools for studying atomic species; this work will characterize molecular species in the plasma instead. With arrays of sensor cells at different pressures, it may be possible to establish a fingerprint for specific compounds or classes of compounds. Plausible applications include detection of gas chromatograph effluents, remote sensing of noxious vapors, and process control.
