Supercritical Carbon Dioxide Injection in Supersonic Beam Mass Spectrometry

摘要

Supercritical fluid injection of CO2 molecular beams can provide sufficient cooling to allow reasonably sharp spectral features for identification in chemical analysis. The attractive feature of this method is that low temperatures can be used to dissolve nonvolatile or thermally labile molecules into a supersonic jet. Although the spectra obtained in expansions of high pressure Carbon dioxide are not as sharp as with Ar carrier gas, the cooling is sufficient to cool out the broad structureless rotational contours observed at room temperature. The use of the mass spectrometer allows identification of each compound by mass analysis in conjunction with the spectroscopic identification achieved by laser spectroscopy. (Reprints)