Theoreticali Investigation Of Functional Large Fullerene C₁₀₆

Because fullerene has a novel structure that electrons form delocalized system, ithas been applied in many fields, such as medicine, energy and astronomy. As forendohedral fullerene, it has much charming properties due to charge transfer fromencapsulated atom(s) to fullerenes. The investigation about high fullerene Cn(n>100) isscarce in both experiment and theory. In this work, isomers of fullerene C106satisfiedwith the IPR and Gd2@C106were investigated in detail by using density functionaltheory(DFT), we hope to strengthen the understanding of electronic strctures andproperties for this kind of large fullerenes through our investigations.Structure geometries were optimiezed through B3LYP functional and the relativethermodynamic concentrations of10C106isomes were got within4000K based on theharmonic vibrational calculations. It was found that the concentrations of the most twostable isomers decrease constantly in the whole temperature region, both of the isomersare more overwhelming than other isomers, indicating that the two isomers arethermodynamic stable and likely to be synthesized and discovered in experiment.Moreover, the IR and RAMAN spectra of the twenty most stable isomers werecalculated, and some characteristic peaks were inditified. NICS calculations show thatC2:063in the20most stable isomers exhibites weak anti-aromaticity while others havelarge aromaticity. The nonlinear optical properties of the five most stable fullereneisomers were investigated along with the different external fields. The results show thatthe maximal responses of THG, EFISH and TPA of Cs:0526are bigger than other fourisomers and C2:0343has bigger maximum in the DFWM process.To elucidate the properties of endohydral fullerenes, the structures of C106with6negative charge were optimized and two Gd atoms were put into the cage of most stablefive fullerenes. The results show that the positions of the two metal atoms in the cageare different and the most energetically stable isomers are different from pure fullerenes.There are three characteristic absorption peaks in the IR spectra for the fullereneisomers. Finally, the most thermodynamic stable endohydral isomer should be Gd2@C106(C1:0984), which is considered to be synthesized much easily usingexperimental means.