Dipole-bound anions of glycine based on the zwitterion and neutral structures

The instability of the zwitterion structure of glycine is significantly red uced by the attachment of an excess electron as a result of which a local m inimum develops on the anionic potential energy surface for the zwitterion structure. However, the global anionic minimum, which is lower by 9 kcal/mo l, corresponds to a singly hydrogen-bonded nonzwitterion structure. The ver tical electron detachment energies for these two dipole-bound zwitterion an d nonzwitterion structures are 3175 and 668 cm(-1), respectively.