The recent experimental data of THG (third harmonic generation) spectr
um chi(3)(omega) of Pt-Cl complex is well interpreted by the present t
heory based on CDW model, which not only shows that the observed peak
around 1.8eV is produced by the two-photon resonance between the botto
m of valence band and the top of conduction band, but also predicts th
at there exists one more peak at 0.9eV outside the observed region.