Endohedral metallo [80] fullerene interactions with small polar molecules

The interaction of M@C80 (M = Li, K and Na) with small polar molecules (H2O, CH3OH, HF and NH3) is described by density functional theory (DFT) calculations. Our theoretical studies show that in several computed cases the binding energies of M@C80 complexes with small polar molecules increases upon encapsulation. The observed behavior can be accounted for by charge transfer effects between the encapsulated metal and the surface of the C80 cage. These assertions have been solidified by a corresponding analysis of the thermochemistry, vibrational frequencies and HOMO molecular orbital plots of the optimized species.