Alkynyl‐Protected Bimetallic Nanoclusters with a Hybrid Mackay Icosahedral Ag42Cu12Cl Kernel and an Octahedral Ag22Cu12 Kernel

Abstract A facile strategy that directly reduces alkynyl‐silver precursors and copper salts for the synthesis of bimetallic nanoclusters using the weak reducing agent Ph 2 SiH 2 is demonstrated. Two alkynyl‐protected concentric‐shell nanoclusters, (Ph 4 P) 2 [Ag 22 Cu 12 (C≡CR) 28 ] and (Ph 4 P) 3 [Ag 42 Cu 12 Cl(C≡CR) 36 ] ( Ag 22 Cu 12 and Ag 42 Cu 12 Cl , R=bis(trifluoromethyl)phenyl), were successfully obtained and characterized by single‐crystal X‐ray diffraction and electro‐spray ionization mass spectrometry. For the first time, a hybrid 55‐atom two‐shell Mackay icosahedron was found in Ag 42 Cu 12 Cl , which is icosahedral M 54 Cl instead of M 55 . The incorporation of a chloride in the metal icosahedron contributes to the stability of the cluster from both electronic and geometric aspects. Alkynyl ligands show various binding‐modes including linear “RC≡C−Cu−C≡CR” staple motifs.