Theoretical Study on a Supramolecular Dimeric Structure Constructed by Metallofullerene Y₃N@C₈₀ and Figure-of-Eight Nanoring

A new supramolecular complex with a dimeric structure(2Y(3)N@C-80 subset of OPP) constructed by metallofullereneY(3)N@I (h)-C-80 and figure-of-eightmolecular nanoring of oligoparaphenylene (OPP) was investigated usingdispersion-corrected density functional theory (DFT-D3). The interactionsbetween the Y3N@I (h)-C-80 guest and the OPP host were studied theoretically at the B3LYP-D3/6-31G(d)similar to SDDlevel. By analyzing geometric characteristics and host-guestbinding energies, it is revealed that the OPP is an ideal host moleculefor the Y3N@I (h)-C-80 guest. Typically, the OPP can well induce the orientation of theendohedral Y3N cluster on the plane of nanoring. Meanwhile,the configuration of the dimeric structure demonstrates that OPP presentsexcellent elastic adaptability and shape flexibility during the encapsulationof Y3N@I (h)-C-80. Highlyaccurate binding energy suggests that 2Y(3)N@C-80 subset of OPP (similar to-443.82 kJ mol(-1) atthe omega B97M-V/def2-QZVPP level of theory) is an extremely stablehost-guest complex. Thermodynamic information indicates thatthe formation of the 2Y(3)N@C-80 subset of OPP dimeris thermodynamically spontaneous. Furthermore, electronic propertyanalysis reveals that this dimeric structure has a strong electron-attractingability. Energy decomposition and real-space function analyses ofhost-guest interactions reveal the characteristics and natureof the noncovalent interactions in the supramolecules. These resultsprovide theoretical support for the design of new host-guestsystems based on metallofullerene and nanoring.