The silane–methane dimer revisited: more than a dispersion-bound system?

Abstract

We present here a comprehensive computational and theoretical analysis of the silane–methane dimer with the goal of understanding the origin of the interactions that hold it together and the factors that affect its strength. Several interaction topologies have been analysed and the associated interaction energies have been evaluated at the CCSD(T)/aug-cc-pVTZ level of theory. Next, substitution effects have been studied on several silane and methane derivatives. The molecular electrostatic potential (MEP) maps of the molecules involved in the interactions have been built to try to correlate the interaction energies with the maximum/minimum EP values (V_s). Furthermore, we have performed an energy decomposition analysis to gain deeper insight into the physical nature of the interactions and to unravel whether dispersion is the primary component of the attraction. Finally, we complete the theoretical analysis with the study of several experimental crystal structures in which there are silyl⋯methyl short contacts.