The molecular structure of disulfiram and its complexation with silica. A quantum chemical study

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Thomas Sandberg, Jessica Rosenholm, Matti Hotokka
Publisher: Elsevier
Publication year: 2008
Journal: Journal of Molecular Structure: THEOCHEM
Volume number: 861
Issue number: 1-3
Start page: 57
End page: 61
eISSN: 1872-7999


Abstract

The complexation between disulfiram, more commonly known by trade names such as Antabus or Antabuse, and amorphous silica was studied by quantum chemical calculations due to extensive adsorption observed experimentally. The conformational behavior of the drug molecule was studied computationally at molecular mechanics (MM), Hartree-Fock (HF)/6-31G∗ and DFT/B3LYP/TZVP level. Two almost equally stable conformers were observed with the energy difference of only 0.8 kJ/mol when comparing the Gibbs’ free energies (δG) at 25 °C. The Mulliken and Löwdin charges and the charges based on an electrostatic potential fit (ESP) were studied at HF/6-31G∗ level.

Protonation of the optimized structures and complexation with geminal silanols were studied at DFT/B3LYP/TZVP level of theory in combination with the MARI-J approximation. Three groups of protonated structures were obtained and the proton affinity of the most stable protonated structure was calculated to 957.6 kJ/mol. In the complexation study four different kinds of complexes did converge. The BSSE-corrected electronic complexation energy of the most stable complex was calculated to −13.6 kJ/mol.


Keywords

conformation, DFT, disulfiram, proton affinity, silica complex

Last updated on 2019-21-07 at 07:10