Complexes of chromium(II) halides with triphenylphosphine oxide

Abstract

Complexes of divalent chromium of the type CrX₂,2Ph³PO, with X = Cl, Br, I, have been prepared. With X = Br, two forms exist. The spectra of CrCl2,2PhsPO and the green form of CrBr₂,2Ph₃PO indicate tetragonally distorted six-coordination of the chromium(II), with bridging through the halogen atoms. The spectra of the yellow form of CrBr₂,2Ph₃PO and Cr12,2Ph8P0 suggest that these compounds have flattened tetrahedral coordination about the chromium(II). Spectra are reported for the six-coordinate complexes CrI₂,2Ph₃PO,2THF, CrBr₂,2THF, and CrBr₂,2CH₃CN, and X-ray powder data are reported for the last two compounds. All the compounds reported have magnetic susceptibilities following the Curie-Weiss law, with values of θ between 8 and 34° and values of μ_eff in the range 4.79-4.88 B.M.