STUDY OF MUTUAL INFLUENCE OF HYDROGEN-BONDS IN COMPLICATED COMPLEXES BY LOW-TEMPERATURE H-1-NMR SPECTROSCOPY

H-1 NMR spectra of various acid-base complexes of different stoichiometry at 100-120K in freon mixtures have been obtained. The separate signals of non-equivalent OH-protons, involved in different H-bonds, have allowed us to consider the problem of the mutual influence of these bonds, using a correlation between the delta(OH) chemical shift and the DELTA-H H-bond enthalpy. The mutual strengthening of H-bonds in complexes of the AH...AH...B type and their weakening in AH...B...HA complexes have been found, the value of the effect being about 10-30%