Gas-Phase Radical Ion Formation from Protonated 1-Methyl-4-nitrosopiperazine: An ESI-MS/MS, Broken-Symmetry DFT, and Multireference Study
The formation of odd-electron radical ions (open-shell) from even-electron precursor ions (closed-shell) in electrospray ionization (ESI) tandem mass spectrometry (MS) represents a violation of the “even-electron rule” and has been observed in several classes of compounds. Such processes often involve homolytic bond...