Photoelectron spectroscopy of the parent anions of the nucleotides, adenosine-5′-monophosphate and 2′deoxyadenosine-5′-monophosphate

The parent anions of the nucleotides, adenosine-5'-monophosphate (AMPH) and 2'deoxyadenosine-5'-monophosphate (dAMPH) were generated in a novel source and their photoelectron spectra recorded with 3.49 eV photons. Vertical detachment energy (VDE) and the adiabatic electron affinity (EA(a)) values were extracted from each of the two spectra. Concurrently, Kobylecka [J. Chem. Phys. 128, 044315 (2008)] conducted calculations which explored electron attachment to dAMPH. Based on the agreement between their calculated and our measured VDE and EA(a) values, we conclude that the dAMPH(-) anions studied in these experiments were formed by electron-induced, intramolecular, (barrier-free) proton-transfer as predicted by the calculations. Given the similarities between the photoelectron spectra of dAMPH(-) and AMPH(-), it is likely that AMPH(-) can be described in the same manner.