Estimating the energy of intramolecular hydrogen bonds in chitosan oligomers

Abstract

The effect the number of chitosan monomer units CTS_n (n = 1–5), the protonation of chitosan dimers, and the interaction between CTS_n (n = 1–3) and acetate ions have on the energy of intramolecular hydrogen bonds is investigated by means of QTAIM analysis and solving the vibrational problem within the cluster-continuum model. It is established that the number of H-bonds in CTS_n is 2n − 1 and the total energy of H-bonds grows by ~20 kJ/mol. It is concluded that the hydrogen bonds between CTS and acetate ions play a major role in the stabilization of polyelectrolyte complexes in dilute acetic acid solutions of CTS.