Strategies towards the purposeful design of long-range ferromagnetic ordering due to spin canting

The magnetic properties of three octahedral iron(II) complexes with Schiff-base like equatorial N2O2 coordinating ligands and methanol (MeOH) or 4,4′-bipyridyl (bipy) as axial ligands are reported. The methanol adduct 1(MeOH) ([FeL1(MeOH)](MeOH); with L1 = [3,3′]-[3,4-pyridinebis(iminomethylidyne)bis(2,4-pentanedionato)(2-)-N,N′,O2,O2′] shows a strong spontaneous magnetization at low temperatures. The complexes 2(MeOH)0.5 ([FeL1(bipy)](MeOH)0.5) and 3(MeOH) ([FeL2(MeOH)2](MeOH); with L2 = [3,3′]-[1,2-phenylenebis(iminomethylidyne)bis(2,4-dioxo-4-phenylbutane)(2-)-N,N′,O2,O2′] show no indication for some long-range magnetic ordering. Results from X-ray structure analysis of all three complexes indicate that the strong spontaneous magnetization of 1(MeOH) is due to spin canting with a canting angle near 90°.

A new modification of N2O2 coordinating Schiff-base like ligands allows the synthesis of a 1D zigzag chain with a strong spontaneous magnetization due to spin canting.Figure optionsDownload as PowerPoint slide