Higher Coordination Numbers of the Typical Elements

Abstract

AbstractThe bonding in electron‐deficient molecules, e.g. the boron hydrides and certain metal alkyls, and in molecules which appear to violate the rare gas rule, e.g. hydrogen bonded complexes, interhalogen compounds and compounds of the typical elements with high coordination numbers such as PCI5 and SF6 can be described by a simple molecular orbital treatment involving delocalized α‐bonds. The contribution of d‐orbitals to the bonding in the interhalogen compounds and rare gas fluorides is very small. The stereochemistry and physical properties of the PX5 system are explained readily by the delocalization treatment and it is likely that here also the importance of spd hybridization has been overemphasized in the past.