Single-Crystal Electronic And Electron-Spin Resonance-Spectra Of Catena-Mu-Bis(1,2-Diphenylphosphinyl)Ethane Dichlorocopper(Ii)

The polarized single-crystal electronic and ESR spectra of catena-μ-bis(1,2-diphenylphosphinyl)ethane dichlorocopper (II) have been recorded. The correlation of the g -factors and the crystallographic data establishes a d xy ground state for the CuO 2 Cl 2 chromophore. The origin of a 14° misalignment of the g -factors and of the extinction directions of the electronic spectra in the ac-plane are discussed and reasons are given for assigning the electronic spectra in D 2 symmetry to yield a tentative one-electron orbital sequence d xy > d yz > d xz > d x 2 - y 2 ≈ d z 2