Gas-phase solvation of Cl −, NO 2−, CH 2NO 2−, CH 3NO 2− and CH 3NO 4− by CH 3NO 2

Abstract

The gas-phase clustering reactions in the systems containing nitromethane were investigated with a pulsed electron-beam high-pressure mass spectrometer. The thermochemical stabilities, Δ H° n−1, n and Δ S° n−1, n , of cluster ions X −(CH 3NO 2) n ( n≤4), X=Cl, NO 2, CH 2NO 2, CH 3NO 2 and CH 3NO 4, were determined. For CH 3NO 4 −(CH 3NO 2) n , the binding energies are found to be significantly lower than those in corresponding cluster ions having Cl −, NO 2 −, CH 2NO 2 − and CH 3NO 2 − as the core ions. This is ascribed to the dispersion of negative charge in the CH 3NO 4 − core ion for which the methyl-peroxynitrate structure is postulated.