Electric dipole moment and charge transfer in alkali-C molecules

Abstract:

We have measured the electric dipole moment of isolated alkali-C₆₀ molecules (with alkali = Li, Na, K, Rb, and Cs) by molecular beam deflection experiments. The dipole increases from 12.4 D for LiC₆₀ to 21.5 D for CsC₆₀. These results are compared to those deduced from an analytical polarizable-ion model. This comparison shows that there is a strong electron transfer from the alkali atom to the C₆₀ cage, which is almost complete for KC₆₀ and RbC₆₀.