Integrated Desorption Mass Spectroscopy: A New Technique for Surface Chemistry.

Integrated desorption mass spectroscopy (IDMS) is a simple yet powerful technique for studying the gas phase products of surface chemical reactions. Data is collected by summing a series of complete mass spectra obtained with a quadrupole mass spectrometer controlled by a personal computer based multichannel scalar card. Signal-to-background levels are extremely high as the spectra are recorded and summed during the entire desorption process. Accurately measured cracking patterns can be used to determine the chemical identity of individual compounds or mixtures of desorbing species. The desorption of trace impurities can also be detected readily. The advantages of this technique as well as several examples are discussed.