New 2p‐3d‐4f Chain Compounds [LnZn(hfac)5(NIT‐Pyrim)2] constructed from Pyrimidine based Nitronyl Nitroxides

The 1:1:2 mixture of Ln(hfac)3, Zn(hfac)2, and NIT‐Pyrim (hfac = hexafluoroacetylacetonate, NIT‐Pyrim = 2‐pyrimidine‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide) afforded a series of 2p‐3d‐4f magnetic chains [Ln(hfac)3Zn(hfac)2(NIT‐Pyrim)2] [LnIII = Gd (1), Ho (2), Yb (3)], in which Zn(hfac)2 and Ln(hfac)3 units are bridged by pyrimidine substituted nitronyl nitroxides through their NO moieties and pyrimidine nitrogen atoms. These complexes represent the first examples of 2p‐3d‐4f complexes with ZnII ions. Magnetic studies show that there exist ferromagnetic exchange couplings between the coordinated NO groups of radical ligands and the GdIII ions.