Decay Kinetics from $\text{}^{4}$I $\text{}_{9}\text{}_{/}\text{}_{2}$ State of Mixed 2,6 Pyridine Dicarboxylate-Acetylacetonate Complexes

The $\text{}^{4}$I $\text{}_{9}\text{}_{/}\text{}_{2}$ → $\text{}^{4}$I $\text{}_{15}\text{}_{/}\text{}_{2}$ luminescence decay curves for a series of complexes Er(pdc)$\text{}_{n}$(acac)$\text{}_{3-n}$ (pdc = pyridine-2,6-dicarboxylate, acac = acetylacetonate, n = 0, 1, 2, 3) as solids and in dilute aqueous solutions have been investigated. The decays are multiexponential, possible reasons for this and for the short lifetimes observed are discussed.