Solid State Synthesis and Optical Limiting Effect of Two Heteroselenometallic Cubane-Like Clusters (μ3-MoSe4)M3(PPh3)3Cl (M = Cu and Ag)

Heteroselenometallic cubane-like clusters (μ 3 -MoSe 4 )M 3 (PPh 3 ) 3 Cl (M = Cu ( I ) and Ag ( II )) were synthesized by the reactions of [Et 4 N] 2 [MoSe 4 ] and M(PPh 3 ) 3 Cl in solid state for nonlinear optical studies. Their optical responses to the incident light exhibit strong optical limiting effect with thresholds of 1.8 J/cm 2 for cluster I and 0.8 J/cm 2 for cluster II in a 0.5 Hz repetition rate condition with nanosecond-duration laser pulses at 532 nm. The optical limiting power of II was testified to be an effective broad band optical limiter with the 1064 nm wavelength laser pulses from the nanosecond Na:YAG laser. In this respect, cluster II is obviously better than cluster I and C 60 . The nonlinear responses for the two clusters in CH 2 Cl 2 have been studied in a picosecond time-resolved pump−probe experiment. The heavy atom effect to the efficiency of nonlinear absorption was also discussed.