Preparation and photoelectron spectrum of the glycine molecular anion: Assignment to a dipole-bound electron species with a high-dipole moment, non-zwitterionic form of the neutral core

We report the gas-phase preparation of negatively charged glycine as well as the Gly.(H2O)(1,2)(-) complexes by entrainment of the neutral precursor into an ionized supersonic expansion tuned to optimize the (H2O)(n)(-).Ar-m clusters. The photoelectron spectrum of Gly(-) displays the signature of a dipole-bound species, with sufficient vibrational fine structure to characterize the core neutral as a higher energy, non-zwitterionic isomer of the amino acid. (C) 2004 American Institute of Physics.