[1] No Illinois Univ, Dept Chem & Biochem, De Kalb, IL 60115 USA
[2] No Illinois Univ, Ctr Biochem & Biophys Studies, De Kalb, IL 60115 USA
[3] FOM Inst Plasma Phys, NL-3439 MN Nieuwegein, Netherlands
[4] Univ Amsterdam, NL-1098 XH Amsterdam, Netherlands
[5] Radboud Univ Nijmegen, FELIX Facil, Inst Mol & Mat, NL-6525 AJ Nijmegen, Netherlands
[6] York Univ, Dept Chem, Toronto, ON M3J 2R7, Canada
[7] York Univ, Ctr Res Mass Spectrometry, Toronto, ON M3J 2R7, Canada
[8] Sandia Natl Labs, Livermore, CA 94550 USA