Residual Dipolar Couplings in 31P MAS Spectra of PPh 3 Substituted Cobalt Complexes

Summary.  Residual dipolar couplings between ³¹P–⁵⁹Co spin pairs were studied in ³¹P MAS spectra of mono- and dinuclear cobalt-triphenylphosphine complexes. These spectra can provide important informations such as the scalar coupling between the dipolar phosphorus and the quadrupolar cobalt nuclei normally not available from solution phase studies. In case of complementary (NQR or X-ray) data even the relative orientation of the interacting shielding, dipolar, scalar couplings, and electric field gradient tensors or internuclear distances can be determined. Examples are shown both for well resolved and practically unresolved cases, factors which possibly control the spectral resolution are discussed in detail. E-mail: gabor.szalontai@sparc4.mars.vein.hu Received June 7, 2002; accepted June 29, 2002