Syntheses and luminescent properties of a series of new lanthanide azelates

Abstract

A series of new lanthanide azelates [Ln(aze)(Haze)(H2O)]·H2O {Ln = La (1a), Ce (1b), Pr (1c); H2aze = azelaic acid}, [Ln2(aze)3(phen)2]·H2O [Ln = Nd (2a), Er (2b); phen = 1,10-phenanthroline], [Sm(aze)(Haze)(phen)]·2H2O (3), [Gd(aze)(phen)2]·ClO4 (4) and (Hphen)[Tb2(aze)2(phen)4]·3ClO4 (5) were hydrothermally prepared and structurally characterized.1a-c are isostructural and show 3-D framework based on 1-D infinite [Ln-O-Ln]n chain. 2a-b exhibit sql layer, while 3 displays 1-D chain, where phen ligands locate at both sides of the chain. The Ln3+ ions of 4 and 5 are connected by aze2− into two different types of rare cationic 1-D chains. The luminescent investigations show that both 2a and 2b exhibit interesting NIR luminescence and 5 displays a good potentiality as a luminescent sensor targeted for Fe3+ ion. Of particular interest, lanthanide azelates have not been to date documented, while this work presents the only examples of lanthanide azelates exhibiting luminescent properties. The magnetic properties of some lanthanide azelates were also investigated.