Photophysical and optical power limiting behaviors of Au(I) acetylides with diethynyl aromatic ligands showing different electronic features

Three Au(I) acetylides have been prepared by coupling (PPh₃)AuCl to the diethynyl aromatic ligands with different electronic features under mild condition. Their photophysical properties and optical power limiting (OPL) behaviors have been investigated in detail. The emission characters of the Au(I) acetylides can vary dramatically by exhibiting either singlet or triplet emission signal through changing the chemical structures of the diethynyl aromatic ligands. In addition, the OPL behaviors of the Au(I) acetylides are also affected by the diethynyl aromatic ligands to show different OPL mechanism. It has been shown that the diethynyl aromatic ligand with neither electron-rich nor electron-deficient features should benefit the OPL performance of the Au(I) acetylides in view of both OPL activity and transparency. Furthermore, the Au(I) acetylides can show comparable or even better OPL performances than the state-of-the-art C₆₀, indicating their great potential in the field of laser protection. All the obtained results should provide valuable information for design high performance OPL materials based on Au(I) acetylides.