NIR luminescence of one-dimensional tartaric acid derivatives neodymium coordination polymers

A series of four neodymium coordination polymers (CPS), namely, {[Nd2L3(CH3OH)(3)(H2O)(4)]}(n)(1), {[Nd2L3(CH3OH)(4)(H2O)(3)]center dot 4CH(3)OH center dot H2O}(n)(2), {[Nd2L3(CH3OH)(4)(H2O)(3)]center dot 4CH(3)OH center dot H2O}(n)(3) and [NdL'(3)-(CH3OH)(3)]n(4) have been isolated by facile reactions of ligands (H2L = L-di-2-thenoyltartaric acid and H2L' = L-di-p-toluoyl-tartaric acid) with NdCl3 center dot 6H(2)O at ambient temperature depending on the reaction conditions. X-ray crystallographic analysis reveals that all complexes 1-4 feature one-dimensional (1D) network structure in which the Nd3+ ions are bridged by carboxylate groups of ligands by five types of coordinated modes. Complexes 1-3 feature one-dimensional (1D) ladder-like chain structure and complex 4 features one-dimensional (1D) linear structure owing tothe ligands coordination modes. NIR luminescence analysis reveal that all complexes 1-4 exhibit three characteristic bands around 890, 1054 and 1326 nm of Nd3+ ion in which complex 3 shows the longest lifetime and highest quantum yield. The energy transfer processes among ligands, the Nd3+ ion and the auxiliary ligand in complexes 1-4 has been investigated. (C) 2016 Elsevier B.V. All rights reserved.