ELECTRON-IMPACT IONIZATION OF C-60 REVISITED - CORRECTED ABSOLUTE CROSS-SECTION FUNCTIONS

We report corrected absolute partial ionization cross sections for the various ions produced by electron impact on C-60. The correction take s into account ion losses due to metastable fragmentation processes wh ich occur during the flight time of the ions from the ion source to th e detector in a two-sector-field mass spectrometer. Due to these ion l osses, previously reported absolute partial and total ionization cross -sections were too small by factors ranging from 1.025 to 2. The corre cted cross-sections reported here are in good agreement with cross-sec tions recently reported by two other groups using experimental techniq ues which are largely insensitive to ion losses caused by metastable d ecay processes. (C) 1998 Elsevier Science B.V. All rights reserved.