Emission spectra from the D-5(1) excited state of the compounds containing Eu3+

Excitation, photoluminescence, and time-resolved emission spectra of the Eu3+-containing compounds, YxEu2-x(CHDC)(3), Eu(NO3)(3)center dot 5H(2)O, and Eu2O3 were obtained. The coordination polymers, R-2(C8H10O4)(3), (R = Eu or Y), were synthesized by mid-temperature hydrothermal technique with the 1,4-cyclohexanedicarboxylate (C8H10O4, CHDC) ligands. Blue-shift emission signals were observed in the emission spectra of these Eu3+-containing compounds at 561 nm excitation. Power dependence and temperature dependence experiments indicate the blue-shift emission results from one-photon hot band transition to the D-5(1) excited state. The Eu3+ 5D1 -> F-7(J) emission decay curves and D-5(0)-> F-7(J) emission rising curves of these compounds were acquired. The D-5(1) state emission lifetimes are quite different in these compounds and are correlated with the D-5(1) -> D-5(0) relaxation rates. Our analysis shows two possible (Eu3+-Eu3+ and Eu3+-CHDC) cross-relaxation processes that relax D-5(1) to D-5(0) with different rates in these compounds.