The experimental, as well as theoretical, values for the frequency-dependent hyperpolarizability of ${\mathrm{C}}_{60}$ differ by orders of magnitude. We present the first density functional calculation of a molecular frequency-dependent hyperpolarizability. Our implementation is very economical, enabling the treatment of molecules of this size, in a potentially much more accurate way than can be obtained with alternative methods. Our results strongly support the recent results by Geng and Wright, who report much lower experimental values than previous authors.

• Received 18 February 1997

DOI:https://doi.org/10.1103/PhysRevLett.78.3097