The nonlinear optical refraction of the metal cluster MoS4Cu4(SCN)2(NC5H5) 6 was studied with the Z-SCAN technique by using 40 ps laser pulse at the wavele ngth of 532 nm. A self-focusing property for the solution of MoS4Cu4(SCN)2(NC5H5 )6 in DMF was observed. The nonlinear refractive index was n2=3.1×10-14 cm2·W-1. Compairing with early results, this sample showed a self-defocusing property at the same wavelength by using 7 ns laser pulse. The optical limiting properity was also studied by using same condition.
