On the fragmentation pathway of the ionized enol of glycine in the gas phase

density Functional and second order many body perturbation approaches were used to compute the poyential energy surface for the fragmentation of the ionized enol of glycine [h2NCH=C(OH)2]+. into water and aminoketene radical cation [H2N-HC=CO]+. two possible pathways were considered. The potential energy surfaces obatained are very similar and both predict the existence of a molecular complex in which the water is coordinated to the amino ketene moiety in two different fashions with a noticeable binding energy. The fragmentation is kinetikally controlled by the step in which the molecular complex s formed from the most stable cation enol of glycine. Our quantum-mechanical data confirm the hypothesis that the ylide ion [H3NCHCOOH]+. is an intermediate in the water loss.