A heterometallic Ni2Gd2 complex : Synthesis, structure and magnetic properties

A novel tetranuclear complex [Ni2Gd2(L)2(CH3COO)2(NO3)2](NO3)2·6H2O·4MeOH (1) with a nitrate ion coordinating in a manner observed until now only in polymeric structures was obtained. The NO3− anion acts both as chelating (chelates to the Gd(III) ion) and bridging (between Ni(II) and Gd(III)) ligand and it also links the two symmetrically dependent parts of molecules into one tetranuclear unit through the short bridge between GdIII and GdIII cations. In 1 the ferromagnetic interactions between Ni(II) and Gd(III) (JNi–Gd = 0.6(2) cm− 1) as well as Gd(III) and Gd(III) (JGd–Gd = 0.5(1) cm− 1) ions are observed.