Luminescence quantum yield approximation

All of the ruthenium polymers show emission when excited at (absorption). A large Stokes shift and a small quantiun yield characterize the emission behavior the luminescence quantum yield of the polymers is 1%. Thermo-gravimetric analyses in air indicate high thermal stabihty of the polymers, with thermal decomposition starting at approximately 290 °C. The polymers have no glass transition temperature. 

Terbium clathrochelate showed green emission of very high intensity. The emission spectrum contains the D4 —> Fj transition bands of the encapsulated terbium ion. The same but less intense emission spectrum was observed at higher temperatures. The luminescence quantum yield is close to 1 at 4.4 K and is approximately 0.05 at room temperature [390]. The decrease in intensity of the terbium(III) ion luminescence starts at 100 K (higher than that of free macrobicyclic tris-bipyridine ligand and lower than that of the corresponding europium(III) compound, Fig. 69). It may be... 

The /3-diketonate [Nd(dbm)3bath] (see figs. 41 and 117) has a photoluminescence quantum efficiency of 0.33% in dmso-7r, solution at a 1 mM concentration. It has been introduced as the active 20-nm thick layer into an OLED having an ITO electrode with a sheet resistance of 40 il cm-2, TPD as hole transporting layer with a thickness of 40 nm, and bathocuproine (BCP) (40 nm) as the electron injection and transporting layer (see fig. 117). The electroluminescence spectrum is identical to the photoluminescence emission the luminescence intensity at 1.07 pm versus current density curve deviates from linearity from approximately 10 mA cm-2 on, due to triplet-triplet annihilation. Near-IR electroluminescent efficiency <2el has been determined by comparison with [Eu(dbm)3bath] for which the total photoluminescence quantum yield in dmso-tig at a concentration of 1 mM is Dpi, = 6% upon ligand excitation, while its external electroluminescence efficiency is 0.14% (3.2 cdm-2 at 1 mAcm-2) ... 

Figure 11.13 The PL spectra from CN-PPP and CN-PPP doped with 5 wt.% of the indicated Eu complexes. All of the films had the same thickness and absorbed approximately the same amount of light, so the emission spectra can be compared to each other to determine relative quantum yields [50]. (Reproduced with permission from M.D. McGehee et al., Narrow bandwidth luminescence from blends with energy transfer from semiconducting conjugated polymers to europium complexes, Advanced Materials, 1999, 11, 1349-1354. Wiley-VCH Verlag GmbH Co. KGaA.)...

Bioluminescence is a special form of chemiluminescence found in biological systems. In bioluminescence, an enzyme or a photoprotein increases the efficiency of the luminescence reaction. Luciferase and aequorin are two examples of these biological catalysts. The quantum yield (e.g., total photons emitted per total molecules reacting) is approximately 0.1% to 10% for chemiluminescence and 10% to 30% for bioluminescence. 

Once water molecules are removed, deuterating the central C-H group of the -diketone further increases the quantum yields and lifetimes by approximately 17% in the ternary complexes. Another source of nonradiative deactivation that should not be neglected comes from diffusing solvent molecules in the second sphere which contain high-frequency C-H vibrations. As a consequence, replacement of toluene with carbon tetrachloride leads to a further slight increase in the luminescence lifetimes of [Yb(dbm-6 i)3(phen)] and [Yb(tta-Ji)3(phen)] (table 10). 

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