ION-MOBILITY MEASUREMENTS OF INORGANIC AND ORGANIC PHOSPHORUS COMPOUNDS

This paper describes the first experiments measuring the mobilities of negative ions produced in various phosphorus-containing gases. An experimental technique is employed whereby α particles from a polonium source produce both a reference pulse from a solid-state silicon barrier detector and thermal electrons which readily become attached to the electronegative phosphorus-containing gas. These mobility measurements were made on a number of inorganic phosphorus halides and organophosphorus compounds at various ratios of E/P0, ranging from 0.5 to 10 V/cm torr. The zero-field reduced mobilities obtained for PCl3, POCl3, PSCl3, PSBr3, isopropyl methyl fluoridophosphonate (Sarin), and diethyl phosphorochloridothionate (DCPT) were 0.39, 0.24, 0.29, 0.41, 0.21, and 0.17 cm2/V sec, respectively. An attempt has been made to explain the nature of the ionic species in terms of the quantum-mechanical theory of ionic mobility as put forth by Dalgarno. This analysis emphasized the need for mass analysis of the ions at the end of their flight path.