A series of new polynuclear lanthanide(III) clusters prepared in alkylol amine

Abstract

A series of new polynuclear lanthanide(III) clusters [Ln4(heda)6(Hheda)2Cl2]Cl4 [Ln = Sm (1a), Eu (1b), Hheda = N-(2-Hydroxyethyl)ethylenediamine] and [Ln6(heda)10(µ-OH)2]Cl6·2H2O [Ln = Y (2a), Gd (2b), Dy(2c), Tb(2d), Ho (2e), Er (2f), Tm(2g)] were solvothermally synthesized and structurally characterized. 1a-b consist of tetra-nuclear lanthanide(III) cluster [Ln4(heda)6(Hheda)2Cl2] built up from two unsaturated [Ln2(heda)3(Hheda)Cl]2+ complex cations via two bridging O atoms of two L− ligands. 2a-g are isostructural and contain hexa-nuclear lanthanide(III) clusters [Ln6(heda)10(µ-OH)2]6+ constructed by the linkages of two unsaturated trinuclear [Ln3(heda)5(µ-OH)] clusters, free Cl− anions as counterions and H2O molecules. Although many transition metal complexes were obtained by using HL ligand as chelating ligand, its polynuclear lanthanide(III) clusters have not been documented to date. 1a-b and 2a-g offer the only examples of polynuclear lanthanide(III) clusters of HL ligand. A preliminary investigation of nine polynuclear lanthanide(III) clusters reveals that the well-known lanthanide contraction has a significant influence on the formation of polynuclear lanthanide(III) clusters under solvothermal conditions. The luminescent properties of 1b and 2d were discussed, and magnetic properties of 1a and 2e were also investigated.