CALCULATIONS OF THE THERMODYNAMIC PARAMETERS OF CLUSTERIZATION OF ALKYL-SUBSTITUTED MELAMINE AT WATER / AIR INTERFACE IN THE FRAMEWORKS OF QUANTUM-CHEMICAL APPROACH

Abstract

In this article, within the semi-empirical quantum chemical software package Mopac2012 (PM3) thermodynamic parameters (enthalpy, entropy, Gibbs energy) of dimers and tetramers clustering of alkyl-substituted melamine 2CnHn+1 (n = 6 – 16) were calculated. A comparison of the corresponding thermodynamic parameters of these structures with the parameters obtained previously for clusters of similar structure, but built on the basis of the other monomer conformation were carried out. It was shown that structures proposed in this article, in comparison with the previous ones, has a lower Gibbs energy of clustering that indicates their energetic preference. Therefore, at this stage, we can assume that the proposed monomer structure underlies the monolayers formed on the water surface by this class of substances.

Keywords

• моношари, термодинамічні параметри, алкілзаміщені меламіну, квантово-хімічний підхід, метод РМ3