Metal Atoms (Li, Na, and K) Tuning the Configuration of Pyrrole for the Selective Recognition of C60

Host-guest structure assembly is significant in the recognition of molecules, and the fullerene-based host-guest structure is a convenient method to determine the structures of fullerenes of which recognition is with many difficulties in experiments. Here, with density functional theory calculations, we designed several crown-shaped pyrrole-based hosts tuned by doping metal atoms (Li, Na, and K) for the effective recognition of C60 with modest interaction between the host and guest. Binding energy calculations showed an enhanced interaction of the concave-convex host-guest system with the doped metal atoms, enabling the selective recognition of C60. The electrostatic interaction between the host and guest was studied by the natural bond order charge analysis, reduced density gradient, and electrostatic potential. Furthermore, the UV-vis-NIR spectra of host-guest structures were simulated to give guidance on the release of the fullerene guest. With much expectation, this work would give a new strategy to design new hosts for effectively recognizing much more fullerene molecules with modest interaction and would be useful for the assembly involving fullerenes.

Automated summary

With density functional theory calculations, crown-shaped pyrrole-based hosts doped with metal atoms (Li, Na, and K) were designed for effective recognition of C60. Enhanced interaction of the concave-convex host-guest system with doped metal atoms enabled selective recognition of C60. The electrostatic interaction between host and guest was studied through natural bond order charge analysis, reduced density gradient, and electrostatic potential. Simulated UV-vis-NIR spectra of host-guest structures provided guidance on the release of the fullerene guest. This work offers a new strategy for designing hosts with modest interaction to effectively recognize fullerene molecules, and is useful for fullerene assembly.