Studies of cyclodextrin chemistry using quantum chemical methods are mainly adopted to investigate the formation of the inclusion complex causing changes in the physicochemical properties of the cyclodextrin guest. In this paper, we conducted a computational modeling study of the inclusion complexes of β-cyclodextrin (β-CD) with m-Methyl Red (m-MR) by using parametric method 6 (PM6), the semi empirical molecular orbital calculations and the natural bond orbital method (NBO).
The paper is devoted to quantum-chemical calculation of tetraethoxysilane (TEOS) structure by different methods: РМ6, Hartree-Fock and DFT. PM6 method was found to be optimal. Kinetic parameters (activation energy and preexponential factor) of hydrolysis of TEOS molecule were evaluated using quantum-chemical calculation. Key words: quantum-chemical calculation, PM6, sol-gel process, tetraethoxysilane, rate constant of hydrolysis.