Ln/Mn-Ln complexes derived from a salicylic azo dye ligand: synthesis, structures, magnetic and fluorescence properties.

Two Ln complexes Ln(HTMSA)(HO)·5.5HO (Ln = Dy (1) and Tb (2), HTMSA = 5-azotriazolyl-3-methoxysalicylaldehyde) and two Mn-Ln clusters [Mn(HO)][MnLn(TTMSA)(HTTMSA)(HO)]·4HO (Ln = Dy (3) and Tb (4), HTTMSA = 5-azotetrazolyl-3-methoxysalicylaldehyde) have been synthesized and structurally characterized. Single-crystal X-ray diffraction reveals that 1 and 2 are isostructural complexes in which the Ln ions are surrounded by six oxygen atoms from three chelate HTMSA ligands and two oxygen atoms from two coordinated water molecules forming a distorted square-anti-prismatic geometry.