An X-ray crystallorgraphic study of the reagent Ph 3 PCl 2 ; not charge-transfer, R 3 P–Cl–Cl, trigonal bipyramidal or [R 3 PCl]Cl but an unusual dinuclear ionic species, [Ph 3 PCl + ⋯Cl – ⋯ + CIPPH 3 ]Cl containing long Cl–Cl contacts

An X-ray crystallographic study of the reagent Ph3PCl2 reveals it to be [Ph3PCl+⋯Cl–⋯+ClPPh3]Cl and not trigonal bipyramidal, molecular charge-transfer Ph3P–Cl–Cl or the simple ionic species [Ph3PCl]Cl; this contrasts with the conclusions from all previous spectroscopic data recorded on compounds of stoichiometry R3PCl2 by earlier workers, and represents the first compound of this formula to be crystallographically characterised.