Poly charge transfer transition

A chemistry of cobalt-sulfide-thiolate molecular clusters comparable with that of iron systems has also begun to emerge. Treatment of [Co4( -SPh)6(SPh)4]2- with HS- in acetone affords the octanuclear cluster [Co8(ji4-S)6(SPh)8]4 isolated as its Pr4N+ salt.988 In MeCN solution the complex is red-purple with intense sulfur-core charge transfer bands which obscure the Co" d-d transitions. This behaviour contrasts with that of both mono- and poly-nuclear cobalt"-thiolate complexes, which all display LMCT bands below 440 nm and have well-developed v2 and v3 features. The [Co8(/j4-S6)]4+ core sustains reversible one-electron oxidation and reduction (E]l2 = —0.54, — 1.18 V, MeCN) and chemical reduction with sodium acenaphthylenide in THF gives [Co8(/r4-... 

The poly-TV-vinylcarbarzole trinitrofluorenone (PVK TNF) charge-transfer complex [21-23] was the first commercial organic photoreceptor used in electrophotography by IBM. The photoconductivity of this material is comparable to that of amorphous selenium, but its utilization in practical devices was limited, owing to its toxicity and long transit-time value, comparable, as for most single-layer photoreceptors, to the development process time. 

Metal to metal charge transfer (MMCT) transition An electronic transition of a bi-or poly-nuclear metal complex that corresponds to excitation populating an electronic state in which considerable electron transfer between two metal centers has occurred. 

Analyses of the Electronic Transitions of Poly(vinyl cinnamate). The concerted cycloaddltlon of clnnamoyloxy group is essentially the reaction of the central double bond. Therefore, we can expect to obtain the clearer image than that hitherto considered in the photochemical reaction if the contributions of the central double bond for the excited states are calculated quantitatively. It is known that the state functions of PPP model can be rewritten to the linear combinations of LE and CT(charge transfer) functions of MIM method(7 ) when we use the same atomic orbitals as the base functions(i ). Using the technique, the state functions in Table 2 are rewritten and the results are collected in Table 3- The relationship between these two methods is illustrated in Fig.1 (b),(c). 

Sandberg et al. examined the effect of light on the FeCls-doped poly(3-nonylthiophene) [161]. The charge transfer bands of the FeCU" anion occurred at 241, 314 and 367 nm. Irradiation of the doped polymer at 367 nm or lower wavelengths resulted in an emergence of the interband transition peak at 480 nm and decreased absorption peaks due to the charge transfer peaks of FeCl4 and the bipolaron bands. The effect of... 

Consideration of the effect of counterion on the p value for addition of poly(styryl)carbanions to DPE is also instructive. The p value increases as the size of the counterion increases, i.e., as the electrostatic interaction of the counterion with the negative charge decreases. This effect would be expected for any transition state structure, since the small lithium cation would be expected to minimize delocalization into the phenyl rings (see Sect. 2.2 of this review and Chap. 1 of [3]). Thus, with the cesium counterion, for any degree of charge transfer onto the 1,1-diphenylcarbon in the transition state, this charge would be more delocalized than for the corresponding lithium system. It would also be predicted that the p value for addition of butyllithium to styrene... 

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