Nonlinear optical response of some isomerically pure higher fullerenes and their corresponding endohedral metallofullerene derivatives: C82–C2ν, Dy@C82 (I), Dy2@C82 (I), C92–C2 and Er2@C92 (IV)

The nonlinear optical response of single isomers of two higher fullerenes, the C82–C2ν and C92–C2 and their dysprosium Dy@C82 (I), Dy2@C82 (I) and erbium Er2@C92 (IV) endohedral derivatives are investigated by means of the optical Kerr effect technique at several excitation wavelengths for the first time. It has been found, that the encapsulation of one atom into the fullerene cage results in enhancement of the second hyperpolarizability, while the incorporation of a second atom results in a decreasing. The presence of resonance contributions is also examined and discussed.