GLOW-DISCHARGE MASS-SPECTROMETRIC ANALYSIS OF NONCONDUCTING MATERIALS

Glow discharge mass spectrometry has been applied to the analysis of n on-conducting materials mixed with a conducting matrix. These material s involve special problems of sample preparation and can produce a com plex plasma with spectral interferences. We have studied several condu cting matrices, including graphite, copper, silver, iron, aluminum and tantalum. Based on spectral simplicity and reduction of oxide ions, t antalum proved best. The effect of metal oxide bond strength on oxide ion formation was determined. Relative sensitivity factors were calcul ated for rare earth elements and a simulated analysis was carried out for these species in a USGS standard reference material.