SYNTHESIS, STRUCTURE, AND MAGNETIC-PROPERTIES OF MIXED-LIGAND COMPLEXES OF MANGANESE AND GADOLINIUM HEXAFLUOROACETYLACETONATES WITH L-2,2,5,5-TETRAMETHYL-3-IMIDAZOLINE-3-OXIDE-1-OXYL NITROXIDE

Complexes of manganese(II) and gadolinium(III) hexafluoroacetylacetona tes with stable nitroxide yl-2,2,5,5-tetramethyl-3-imidazolin-3-oxide- 1-oxyl (L), Mn(hfac)(2)L(2) and Gd(hfac)(3)L(2), have been synthesized . The results of an X-ray study of these complexes (Mn(hfac)(2)L(2) : a = 21.762(4), b = 9.685(1), c = 22.073(3) Angstrom, beta = 114.94(1)d egrees, space group Cc, Z = 4; Gd(hfac)(3)L(2): a = 22.079(4), b = 11. 562(2), c = 21.302(4) Angstrom, beta = 112.25(1)degrees, space group C c, Z = 4) have shown that both compounds have a molecular structure wi th the paramagnetic ligand coordinated via the oxygen atom of the N-ox ide group. According to the results of static magnetic susceptibility measurements, the energies of exchange interactions between unpaired e lectrons oft and of metal ions are less than 1 cm(-1) in magnitude.