“…Palladium is a unique transition metal in that it forms an exceptionally versatile family of high‐nuclearity palladium carbonyl phosphine clusters (i.e., with cores of at least 10 metal atoms with direct metal–metal bonding) that display a truly remarkable diversity of geometries about the metal cores 1a–h. Fifteen distinctly different geometries have been identified crystallographically for Pd n cores with n =10,2a–c 12,2d,e 16,2f,g 23 (two different metal cores have been observed),2h–j 29,2e 30,2k 34,1a, 2l 35,2g 38,2m 39,2g 54,2k 59,2g,n 69,2o and 145 2p. All but two of these highly condensed palladium clusters have close‐packed frameworks that contain metal fragments whose structural units may be described as ccp (cubic close‐packed), mixed ccp/hcp (hexagonal close‐packed) stacking layers (which include layer sequences corresponding to capped octahedra, centered cuboctahedra, or centered anti‐cuboctahedra), and as icosahedra.…”