Synthesis, crystal structures, and magnetic properties of three Mo(V)-Ln(III) (Ln = Ho, Er, Tm) magnetic chains based on [Mo(CN)8]3-

Complexes 1-3 with general formula [Ln(tmphen)2(DMF)2Mo(CN)8]∞ (Ln = Ho(1), Er(2) and Tm(3)) have been prepared by reaction of Cs3[Mo(CN)8]·4H2O and Ln(NO3)3·6H2O in the presence of the tmphen blocking ligand (tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline), and characterized by IR, elemental analysis, single crystal X-ray diffraction and magnetic measurements. The structural determination reveals that complexes 1-3 consist of 1D chains, in which [LnIII(tmphen)2(DMF)2]3+ and [MoV(CN)8]3− ions are linked in an alternating fashion. Furthermore, two adjacent 1D chain are linked by π-π interaction between the benzene and pyridine rings and hydrogen bonds to form a supramolecular three-dimensional framework. Investigation of the magnetic properties of complexes 1-3 reveals antiferromagnetic coupling interaction exists between heavy LnIII (HoIII, ErIII and TmIII) and MoV ions.