Synthesis and Characterization of the Highly Unstable Metalloid Cluster Ag 64 (P n Bu 3 ) 16 Cl 6

The reduction of ( n Bu 3 P)AgCl with LiBH( s Bu) 3 in toluene gives the metalloid silver cluster Ag 64 (P n Bu 3 ) 16 Cl 6 ( 1 ) as dark red, temperature‐ and light‐sensitive single crystals in high yield. 1 is the largest structurally characterized metalloid silver cluster exhibiting chlorine and phosphine substituents only. The silver atoms in 1 show an overall brick‐shape arrangement, where structural resemblance to the close‐packed fcc and hcp structures is realized. Within 1 a 58 electron closed shell system is present. The light sensitivity renders 1 as a model compound for the primary seeds of the photo process, whereby this sensitivity, together with the high‐yield synthesis show that 1 is a perfect starting compound for further investigations like silver‐plating processes.