Spectroscopic studies of the complexes formed between lanthanide ions and N-(2-hydroxyethyl)iminodiacetic acid in solution

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 1998-12, Vol.119 (2), p.109-114
• Main Authors: Hnatejko, Zbigniew, Lis, Stefan, Stryła, Zdzisław, Elbanowski, Marian
• Format: Article
• Language: English
• Subjects: Chemistry; Energy transfer; Europium(III); Exact sciences and technology; General and physical chemistry; Luminescence; N-(2-hydroxyethyl)iminodiacetic acid complexes; Solution properties; Solutions; Terbium(III)
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/S1010-6030(98)00403-1

The solution coordination chemistry associated with 1 : 1 and 1 : 2 complexes of lanthanide ions with N-(2-hydroxyethyl)iminodiacetic acid (HIDA, H 2hida) has been studied by means of luminescence spectroscopy. The luminescence lifetime of Tb(III) in complexes with HIDA have been measured in H 2O and D 2O solutions of varying pH (ranging from pH 1.5 to 11) and lanthanide(III)–HIDA ratio. The lifetime has been used to determine the number of water molecules bound in the inner coordination sphere to the Tb(III) ion. In addition, energy transfer from Tb(III) to Eu(III) in the Ln(III)–HIDA system has been investigated. The results obtained show that HIDA acts as a tetradentate ligand. It was also concluded that at low pH values, the Tb(HIDA) complex is mononuclear and contained an average of ∼5 molecules of coordinated water, whereas at high pH values, this complex is self-associated. The Tb(HIDA) 2 complexes below pH 9 were monomeric and contained one or two coordinated water molecules.