New Method to Analyse IR-Studies of Monomer-Dimer Self-Association: 2,2-Dimethyl-3-Ethyl-3-Pentanol in Carbon Disulfide as an Example

Abstract

Abstract Two new equations have been derived to treat the IR data from the monomer-dimer self-association. Equation (9), in the text, is to regress the integrated absorbances of the monomer bands to determine the molar absorptivity of the monomer band, ε m, and the dimerization constant, K. Equation (13), in the text, is to regress those of dimer band to obtain the molar absorptivity of the dimer band, ε d, and dimerization constant K. The self-association in the dilute solution of 2,2-dimethyl-3-ethyl-3-pentanol in carbon disulfide at different temperatures has been used as an example to demonstrate the usage of these two equations. The discrepancy between the values of K at the same temperature determined either from the monomer band or from the dimer band can be used as a criterion for the goodness of determination. The standard enthalpy and entropy of dimerization have also been obtained via a van’t Hoff plot from the data of K at different temperatures. The advantages of this new approach have also been discussed.