In order to complete the analysis of K and A derivatives, it is instructive to appraise the role of the distance factor The D value tends to be nearly constant in the distinctly separated regions, with the borderlines for the central TS region ca. (-1.5<<1.3). DAB for all contacts involving the mobile H4 atom distinctly increase in the central region, DAB for other contacts are all negligibly small and slightly decreasing around TS; only one, most significant representative of this group has been brought to the picture (N1-H5, Fig. ). 30 and 31 for the selected bonds variable with the internal proton transfer in NH2-CHO.