In-beam ionization by alkali ion attachment applying a two-filament ion source

A simple ion source was constructed for in-beam ionization by alkali ion attachment. A wire probe covered with sample was placed near an alkali ion emitter prepared from a mixture of silica gel and alkali halides. The ionization of various thermally labile compounds and of mixtures was investigated. Na⁺ proved to be the most suitable alkali ion for cationization. For monosaccharides experiments revealed the elimination of water upon ionization by Li⁺ attachment. The experimental set-up was also examined for measuring the heat of sublimation of organic solids.