Synthesis, structure, magnetic properties of one‐dimensional Cu‐Ln chains linked by a nitronyl nitroxide radical with two pyridyl groups

Abstract

Two new Cu−Ln 1D coordination chains with formula [Ln(hfac)3Cu(hfac)2 (NIT‐3Py‐5‐3Py)(H2O)]n (LnIII=Gd 1, Dy 2; hfac=hexafluoroacetylacetonate, NIT‐3Py‐5‐3Py=2‐(5‐(3‐pyridyl)‐3‐pyridyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide) were successfully constructed by means of a new nitronyl nitroxide radical ligand containing two pyridine groups. In these two complexes, the radical ligand binds two CuII ions through its two pyridine groups to produce 1D chain while the aminoxyl moiety of the radical is bound to a Ln (III) ion. Direct‐current magnetic susceptibility investigations indicate that ferromagnetic exchanges are dominant and magnetic susceptibility data of Gd derivative are analyzed using a magnetic model, indicating that Cu‐NO coupling through pyridine group and Gd‐NO direct exchange are ferromagnetic interactions. There is no magnetic relaxation behavior for Dy analogue.