Spectroscopic properties of neodymium(III)-containing polyoxometalates in aqueous solution

Abstract

The spectroscopic properties of the neodymium(III)-containing polyoxometalates (POMs) [Nd(PW 11O 39) 2] 11−, [Nd(PMo 2W 9O 39) 2] 11−, [Nd(PMo 4W 7O 39) 2] 11−, [Nd(PMo 6W 5O 39) 2] 11−, [Nd(SiMo 2W 9O 39) 2] 13−, [Nd(P 2W 17O 61) 2] 17−, [NdW 10O 36] 9−, [NdP 5W 30O 110] 12− and [NdAs 4W 40O 140] 25− are described. Absorption spectra of aqueous solutions of the complexes have been recorded and the transition intensities are parameterised in terms of the Judd–Ofelt intensity parameters Ω λ ( λ = 2, 4, 6). Marked differences were found between the luminescence lifetimes of the complexes of the type Nd(POM) and those of the type Nd(POM) 2, due to a better shielding of the neodymium(III) ions from the bulk water molecules in the latter type of complexes.