Using two new flexible and functional nitronyl nitroxide radicals as
ligands, two？copper
(II) complexes {[Cu(hfac)2]3(NITmPhO3Py)2}n(1) and [Cu(hfac)2(NIToPhO3Py)]2(2) (NITmPhO3Py = 2-[(3-methoxy-pyridinyl)phen-3-yl]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, NIToPhO3Py = 2-[(3-methoxy-pyridinyl)phen-2-ly]-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide,
hfac = hexafluoroacetylacetone), have been characterized structurally and
magnetically. The X-ray crystal analyses showed that complex 1 displayed a chain polymer structure which formed with
{[Cu(hfac)2]3(NITmPhO3Py)2}n due to the cross-linking of two cyclic binuclear fragments{[Cu(hfac)2]2(NITmPhO3- Py)2} via the bridging unit [Cu(hfac)2]; complex 2 presented a binuclear cyclic structure [Cu(hfac)2]2(NIToPhO3Py)2. The magnetic
behaviors of the two complexes 1 and 2 have been investigated.
Magnetic studies showed that antiferromagnetic interactions dominated in
complex 1, while there existed ferromagnetic interactions between Cu(II)
and coordinated NO group in complex 2.
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