Triplet compound

Figure 7.10 (a) A simple triplet and (b) a compound triplet in the spectrum of an alkaline earth... 

A — P transition, shown in Figure 7.10(b), has six components. As with doublet states the multiplet splitting decreases rapidly with L so the resulting six lines in the spectrum appear, at medium resolution, as a triplet. For this reason the fine structure is often called a compound triplet. 

For compounds that are very weakly phosphorescent or that phosphoresce at wavelengths out of the normal range of sensitivity of the spectrometer this method of triplet energy determination cannot be applied. For these compounds triplet energies can sometimes be determined by measuring their E-type or P-type delayed fluorescence. 

Compound Triplet lifetime0 (ps) Relative Compound levels in V79 cells (nmol/106 cells kJ m-2) Fluence for 90% kill of V79 cellsd (kJ m-2)... 

For carbonyl compounds that ordinarily would react in the n,n triplet state, an important reaction which can compete with photocycloaddition is energy transfer to the unsaturated system. When the triplet energy of the unsaturated system is below that of the carbonyl compound, triplet-triplet transfer may take place to the exclusion of oxetane formation. Such is the case when irradiation of a carbonyl compound in the presence of a diene results in isomerization and dimerization of the diene, while no direct photocycloaddition takes... 

Carbonyl compound Triplet energy, kcal mole 1 A/B... 

With both azo compounds triplet decomposition presumably yields two radicals with their spins initially parallel. Since no less cage product is formed than in singlet decompositions, whatever spin inversion needs to take place must occur much more rapidly than diffusion out of the cage. It has been suggested that with the nitrogen molecule initially between the two radicals, the interaction between them is so small that they are effectively free and can couple in the cage as readily as the radicals formed by singlet decomposition.463... 

Spin-orbit coupling not only governs the amount and pattern of ZFS of the emitting triplet state, but it is also of dominant importance for the radiative emission decay rates and thus for the photoluminescence quantum yields. These properties are crucial for the suitability of triplet emitters in OLEDs. In conclusion, detailed spectroscopic studies of compounds triplet state properties in combination with... 

The two unshared electrons in singlet carbenes have opposite spins. Carbenes generated by a-elimination are singlets because the two unshared electrons are derived from the same MO. Triplet carbenes, in which the two unshared electrons have parallel spins, are usually generated by photolysis of diazo compounds. Triplet carbenes are discussed in Chapter 5. 

In both structures, phosphorus has CN 7 and 6. The Re3P4 structure Is a deficient variant of NlAs ( Re3As4) and Is also related to cluster compounds.Triplets of face-condensed Pg octahedra are centered by Re atoms forming linear Reg groups. The octahedra are further connected via common edges. 

YER 11] Yersin H., Rausch A.F., Czerwieniec R. et al., The triplet state of organo-transition metal compounds. Triplet harvesting and singlet harvesting for efficient OLEDs , Coordination Chemistry Review, vol. 255, nos. 21-22, pp. 2622-2652, 2011. 

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