Energy Transfer Between Eu3+ and Nd3+ in Near-Infrared Emitting β-Triketonate Coordination Polymers

Isomorphous<i>β</i>-triketonate-based lanthanoid polymers containing tris(4-methylbenzoyl)methanide (<b>mtbm</b>) and Rb<sup>+</sup>with formula,{[Ln(Rb)(<b>mtbm</b>)<sub>4</sub>]<sub>2</sub>}<i><sub>n </sub></i>(Ln = Eu<sup>3+ </sup>and Nd<sup>3+</sup>) have been synthesised and structurally characterised. The photophysical properties for the Nd<sup>3+</sup>complex presented long lifetimes and relatively high quantum yields in comparison with analogous <i><u>β</u></i>-diketonate complexes. Mixed lanthanoid complexes were also formed and their luminescence properties studied, with effective sensitisation of the <sup>4</sup>F<sub>3/2 </sub>of<sub></sub> Nd<sup>3+ </sup>via the <sup>5</sup>D<sub>0 </sub>of Eu<sup>3+</sup>, which is to the best of our knowledge the first example of Eu<sup>3+</sup>to Nd<sup>3+</sup>sensitisation in a coordination complex or polymer.<br>