Experimental and computational study of the structure and bonding interactions in layered compounds of molybdenum disulfide with guanidine derivatives

Heterolayer MoS 2 compounds with molecules of protonated guanidine (GUA) and its aliphatic derivative 1,5,7- triazobicyclo[4.4.0]dec-5-ene (TABD) are prepared using single-layer dispersion of molybdenum disulfide. The structure of these compounds, including the geometry of sulfide layers and the localization of organic cations, is determined by powder X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, differential scanning calorimetry, and density functional theory (DFT) calculations. The analysis of the topology and energy characteristics of non-covalent bonding interactions within the Quantum Theory of Atoms in Molecules shows that the contribution of NH…S bonds to the stabilization of the heterolayer structure is essential in the compound with GUA and is significantly smaller than the contribution of CH…S contacts in the compound with TABD. Relation between the number and energetics of bonding contacts between the components with the geometry and positions of organic molecules in the interlayer space of MoS 2 is discussed.