The use of molecular electronic structure methods to investigate mechanically interlocked molecules.

Mechanically interlocked molecules (MIMs) show several applications as molecular machines, catalysts, and appear as potential structures for ion recognition. Importantly, the understanding of the nature of the mechanical bonds that support the interaction between the non-interlocked components of MIMs is still a poorly explored topic in the literature. Important discoveries in the field of MIMs have been made using molecular mechanics (MM) and, in particular, molecular dynamics (MD) methods. However, obtaining more accurate geometric and energetic parameters requires the use of molecular electronic structure methods. The present perspective highlights some studies of MIMs using density functional theory (DFT) or electron correlation methods. We expect that the studies highlighted here will show that such large structures can be studied with more precise approaches by selecting the model system to be studied by chemical intuition or supported by low scaling quantum mechanics methods. This will contribute to the elucidation of important properties to be used in the design of various materials.