Optical limiting mechanisms of four hexagonal prism-shaped metal cluster compounds

摘要

Optical limiting (OL) mechanisms of hexagonal prism-shaped metal cluster compounds W2Ag4S8 (dppy)4, Mo2Ag4S8(dppy)4, W2Ag4S8(pph3)4 and Mo2Ag4S8(pph3)4 were investigated by time-resolved pump-probe experiment with picosecond laser pulses at 532 nm. Experimental results indicate that dominant OL mechanism for W2Ag4S8 (dppy)4, Mo2Ag4S8(dppy)4 with ligands (dppy)4 is the cooperation of nonlinear absorption and nonlinear scattering. While dominant OL mechanism for W2Ag4S8(pph3)4 and Mo2Ag4S8(pph3)4 with ligands (pph3)4 is nonlinear scattering only. From the analyses of pump-probe experimental results, we can deduce that OL mechanisms for hexagonal prism-shaped metal cluster compounds are related to the ligands of hexagonal prism-shaped metal cluster compounds.