Mechanism of soft X-ray radiation damage on glycine by XPS

This paper reports the behaviour of radiation damage of solid glycine in a XPS spectrometer equipped with Mg and Al X-ray sources. The main results are as follows: (i) the kinetics of the damage process obeys the first-order rate law, (ii) decarboxylation can be deduced, and (iii) deamination does not occur, but the nitrogen atoms in original molecules are transformed into a new chemical form with higher electron density by photo-reduction.