RARE-EARTH-OXIDE EQUILIBRIA IN PULSED DIRECT-CURRENT GLOW-DISCHARGE MASS-SPECTROMETRY

Glow discharge mass spectrometry is used to examine the equilibria exi sting between La+ and LaO+. A pulsed discharge permitted temporal comp arison of spectra taken at varying intervals after discharge initiatio n. Post-discharge peaks are observed for both atom and oxide ions. By varying the pulse period while sustaining a fixed ''on'' time, the deg ree of deposition of gaseous constituents on the cathode surface can b e controlled. Injection of normal water and isotopically labeled water for compacted and noncompacted samples allows insight into the source of water signals.