Abstract
The nonlinear optical (NLO) properties of fullereneshave attracted great attention recently. However, there is no agreement on the origin of the second‐harmonic generation (SHG) signla, for example. The work reported here could settle this dispute. A theoretical approach to calculating the electric‐dipole, magnetic‐dipole, and electic‐quadrupole transition moments SHG spectra in C60are calculated.