Electron transfer reactions of nitromethane, acetaldehyde and benzaldehyde with (H2O)n−, CO2[rad]−(H2O)n, and O2−(H2O)n, n < 110, in the gas phase

Abstract

The reactions of nitromethane, acetaldehyde and benzaldehyde with hydrated electrons (H2O)n− and the hydrated radical anions CO2−(H2O)n, O2−(H2O)n, with n<110, were studied by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. Electron transfer reactions, with the newly formed radical anion staying in the water cluster, were found to take place for (H2O)n− and CO2−(H2O)n, while O2−(H2O)n were unreactive. The reaction rates for the electron transfer processes were derived assuming pseudo first order kinetics. Thermochemistry was analyzed in the framework of nanocalorimetry. Reaction dynamics governs the measured rates, with benzaldehyde reacting least efficiently. Electron transfer from CO2−(H2O)n is probably associated with a barrier. Hydration seems to stabilize a valence-bound state of CH3CHO(H2O)n−.