plasma desorption mass spectrometry

plasma desorption mass spectrometry [′plaz·mə dē¦sȯrp·shən ′mas spek′träm·ə·trē]

(spectroscopy)

A technique for analysis of nonvolatile molecules, particularly heavy molecules with atomic weight over 2000, in which heavy ions with energies on the order of 100 MeV penetrate and deposit energy in thin films, giving rise to chemical reactions that result in the formation of molecular ions and shock waves that result in the ejection of these ions from the surface; the ions are then analyzed in a mass spectrometer. Abbreviated PDMS.