A series of polycrystalline Li 3 Ba 2 La 3Àx Eu x (MoO 4 ) 8 samples were prepared by the conventional solidstate reaction. The phase formation of the samples was investigated by X-ray diffraction measurements. The luminescence spectra and decay curves were studied as a function of Eu 3+ concentration and temperature. It turned out that the optical band gap of the undoped molybdates is at 3.65 eV. The quantum efficiency (QE) of the Eu 3+ doped luminescent materials increases with increasing Eu 3+ concentration and almost 100% QE was obtained for those samples doped with 70, 80, or 90% Eu 3+ . A sample containing 100% Eu 3+ showed solely a slight decrease in quantum efficiency. The luminous efficacy (LE) was 330 and 312 lm W opt À1 for the 10 and 100% Eu 3+ doped samples, respectively. The decrease of LE values is caused by a slight shift of the colour point to the red spectral range with increasing Eu 3+ content. Temperature dependent measurements revealed that Li 3 Ba 2 Eu 3 (MoO 4 ) 8 loses only 15% of efficiency up to 400 K, which demonstrates that the investigated phosphors are attractive for application in pcLEDs.

Octahedral tungsten iodide clusters equipped with apical ligands (L) are synthesized to implement substantial photophysical properties. The [WI(CFCOO)] cluster reported herein is the first example of a family of ligand substituted [WIL] clusters. Such compounds are expected to exhibit a rich photochemistry in which the apical ligands play a crucial role. The versatile solid state and solution phase photophysical properties of (TBA)[WI(CFCOO)] described herein parallel characteristics obtained in some photophysically active organic compounds, including a broad absorption in the UV/VIS region. Upon irradiation of this compound, a broad red emission is observed in the VIS/NIR region resulting from excited triplet states, and singlet oxygen (aΔ) is generated in the presence of O.

The synthesis, characterization, and luminescence properties of (Bu4N)2[Mo6I8(NCS)6] are reported. Orange crystals of (Bu4N)2[Mo6I8(NCS)6] were crystallized from acetone solution and used for X‐ray single‐crystal structure determination and refinement, yielding a structure with a centrosymmetric [Mo6I8(NCS)6]2– ion. Photoluminescence studies on the crystalline solid revealed a broad excitation in the UV/Vis region and an emission around 690 nm. The red emission intensity decreases with increasing partial pressure of atmospheric molecular O2.

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