Third-Order Susceptibility of Li@C60

Buckminsterfullerene is a conjugated electron-accepting molecule that has potential use in nonlinear optical applications, while the addition of endohedral lithium should transfer charge to the carbon cage, ultimately providing a low potential energy surface for the motion of the Li atom. These authors present a theoretical and experimental investigation into the second hyperpolarizability of Li@C60, and show that the presence of a Li atom inside a C60 cage increases its second hyperpolarizability by an order of magnitude.