Mark Wicholas

Contact shift studies of some paramagnetic octahedral complexes: Diphenylsulfoxide complexes of iron(II), cobalt(II), and nickel(II)

Abstract The proton NMR isotropic shifts of the octahedral diphenylsulfoxide (DPSO) complexes, M(DPSO) 6 (ClO 4 ) 2 , of Fe(II), Co(II), and Ni(II), in CDCl 3 are reported. From a consideration of the magnitude and concentration dependence of these isotropic shifts, it is concluded that the pseudocontact contribution to the isotropic shifts is very important for Co(DPSO) 6 2+ but not for Ni(DPSO) 6 2+ and Fe(DPSO) 6 2+ . Also in the latter two complexes, the unpaired spin is probably delocalized within the ligand by a combination of both σ and π-mechanisms.

Tetrakis[μ-1,3-bis(4-methyl-2-pyridylimino)isoindolinato]trimercury(II) dinitrate methanol tetrasolvate

The title compound, [Hg (C H N ) ](NO ) ·4CH OH, consists of a trinuclear Hg dipositive cation, [Hg (4′-Me ) ] , two nitrate anions and four occluded methanol molecules. The Hg atoms of the cation lie on a crystallographic twofold axis and are tetrahedrally coordinated by nitrogen-donor atoms of the bridging 1,3-bis(4-methyl-2-pyridylimino)isoindoline ligands. The central Hg atom is coordinated by four pyridine N atoms, one from each of the 4′-Me ligands, while the two outer Hg atoms are each coordinated by two pyridine and two pyrrole N atoms.