Numerical results for the elements of the DF connectivity matrix have been obtained from calculation of the IRC energy profile by the standard procedure at the MP2 level using the 6-311++G(3df,3pd) basis set and the Gaussian 09 code. The internal proton transfer reaction has been selected as an example, the preliminary data for the diagonalization of the connectivity matrix have already been reported for this molecule (in RS, TS and PS only). 77,95