Probing Hydrogen-Bonding Properties of a Negatively Charged MoS2 Monolayer by Powder X-ray Diffraction and Density Functional Theory Calculations.

Abstract

The contributions of various noncovalent interactions in stabilization of the assembled and delaminated MoS2–hexamethylenetetramine (HMTA)-layered compound resulted from the assembly of protonated HMTA molecules and negatively charged 1T-MoS2 monolayers have been considered on the basis of powder X-ray diffraction pattern modeling, density functional theory calculations, and atoms in molecules quantum theory analysis. The structure with HMTA cations involved in NH···S bonding with MoS2 layers was concluded to be more advantageous than the alternative one with NH···N bonding between the cations. Delamination was demonstrated to essentially influence the hierarchy of interactions and leads to significant strengthening of the NH···S hydrogen bond established between HMTA and the MoS2 monolayer surface. The method applied in this study for evaluation of the monolayer MoS2 properties on the basis of the 3D structure of the MoS2–organic compound is expected to be helpful to gain insights into the interactions occurring in many MoS2-based systems.