CRYSTAL SUPRAMOLECULARITY - ELABORATE 6-FOLD, 8-FOLD AND 12-FOLD CONCERTED PHENYL EMBRACES IN COMPOUNDS [M(PPH3)(3)](Z) AND [M(PPH3)(4)](Z)

Multiple phenyl embraces are concerted supramolecular motifs based on intermolecular phenyl-phenyl attractions, mainly in the edge-to-face ( ef) geometry. Variations of the six-fold phenyl embrace (6PE) and high er order multiple phenyl embraces involving eight or twelve phenyl gro ups are described. They occur in crystals of metal complexes with thre e or four Ph-3 ligands. The enlarged 6PE (E6PE) involves phenyl groups from three Ph3X ligands in each of two molecules, and is formulated g enerally as (XPh)(3) ...(PhX)(3) : the H6PE, or (XPh)(3) ...(Ph3X), is a hybrid of the E6PE and the 6PE [which is (XPh3)...(Ph3X)]. The 8PE uses {M(XPh2)(2)}...{(Ph2X)(2)M} and occurs in two variants according to whether the XMX planes on the two molecules are approximately paral lel (P8PE) or orthogonal (O8PE). Molecules [M(PPh3)(3)](z) can form a 12PE, which uses {M(XPh2)(3)}...{(Ph2X)(3)M} and includes ten intermol ecular ef interactions. The crystal packing in various compounds conta ining [M(PPh3)(3)](z) or [M(PPh3)(4)](z) is described,and involves eit her multiple instances of one embrace type in high symmetry crystal la ttices or combinations of various multiple phenyl embraces in lower sy mmetry crystal lattices. The current hierarchy of multiple phenyl embr aces is summarised.