Transition metals tris ruthenium

In another approach, implemented with nanofibers based on ionic transition metal complexes [ruthenium(II) tris(bipyridine)] embedded in PEO, inter-digitated electrodes are used instead of sandwich geometries. Fibers are deposited across the gap between electrodes, and injected carriers recombine yielding luminescence from a point source that has sub-wavelength dimensions ( 0.2 x 0.3 pm, Figure 5.11). ... 

Some years later, at the beginning of the 1970s, first ECL system based on the luminescent transition metal complex tris(2,2 -bipyridine)ruthenium(II)-Ru (bipy)32 + -has been reported.11 It was shown that the excited state 3 Ru(bipy)32 + can be generated in aprotic media by annihilation of the reduced Ru(bipy)31 + and oxidized Ru(bipy)33 + ions. Due to many reasons (such as strong luminescence and ability to undergo reversible one-electron transfer reactions), Ru (bipy)32+ later has become the most thoroughly studied ECL active molecule. 

Phospholes can behave as simple two electron donors, in the same way as tertiary phosphines, and most of the transition metals have been complexed to phospholes. For example, ruthenium(II) forms a series of complexes [(Phole)2 Ru(CO)2C12] and [(Phole)3 Ru(CO)C12]. The formation of the tris phosphole complex attests to their small size. Because of the ring structure an unusual isomerism has been observed, with the rings either in the basal plane of the square pyramidal complex or normal to the basal plane (Figure 23). 

In the transition metal polypyridyl complex group, tris(4,7-diphenylphen-antroline) ruthenium(II) (Ru(dpp)2+) is widely used as a probe for a PSP. The luminescence lifetime of Ru(dpp)2+ is long compared with the other ruthe-nium(II) polypyridyl complexes [17]. The absorption and emission maxima of Ru(dpp)2+ are 457 and 610 nm, respectively. The luminescence lifetimes under nitrogen- and air-saturated conditions are ca. 4.0 and 2.0 ps, respec-... 

Dyes such as erythrosin B [172], eosin [173-177], rose bengal [178,179], rhodamines [180-185], cresyl violet [186-191], thionine [192], chlorophyll a and b [193-198], chlorophyllin [197,199], anthracene-9-carboxylate [200,201], perylene [202,203] 8-hydroxyquinoline [204], porphyrins [205], phthalocyanines [206,207], transition metal cyanides [208,209], Ru(bpy)32+ and its analogs [83,170,210-218], cyanines [169,219-226], squaraines [55,227-230], and phe-nylfluorone [231] which have high extinction coefficients in the visible, are often employed to extend the photoresponse of the semiconductor in photoelectro-chemical systems. Visible light sensitization of platinized Ti02 photocatalyst by surface-coated polymers derivatized with ruthenium tris(bipyridyl) complex has also been attempted [232,233]. Because the singlet excited state of these dyes is short lived it becomes essential to adsorb them on the semiconductor surface with... 

Dyads and triads based on the photoactive, multibridging [Ru(bpz)3] (bpz = bipyrazine) complex directly bound to transition metal complexes were obtained by following the procedures previously reported for the generation of symmetric heptanuclear supermolecules (67-69). Such systems contain a tris(bpz)ruthenium (II) ion [RuJ attached to bis(bpy)chlororuthenium(II)/(III) [Rup], or penta-cyanoferrate(II)/(III) complexes via a bpz bridging ligand, as shown for the... 

The contribution of pulse radiolysis to general chemistry is very significant, and this is exemplified by the following studies of transition metal complexes. The reduction of tris(2,2 -bipyridine)ruthenium(III) ion by the hydrated electron was the first example of this type of reaction to show clearly the formation of a product in an electronically excited state [80] ... 

There is much interest in transition metal polypyridyl complexes, largely due to their numerous applications in a variety of fields (247-250). In particular, ruthenium(II) tris(2,2 -bipyridyl) has been one of the most extensively studied complexes of the last decade due to its chemical stability, redox properties, excited-state reactivity, and luminescent emission (251, 252). 

The reactions of iron carbonyls with diorgano tellurides deserve mention, for example the reaction of Fe3(CO),2 with PhjTe gives Ph2TeFe(CO>4, whilst several ruthenium-carbonyl complexes have been prepared from reactions between diphenyl telluride and alcoholic carbon monoxide-saturated solutions of ruthenium trichloride hydrate. Various other ruthenium-carbonyl complexes of diorgano teUurides, including di- and tri-substituted species, have also been described. The utility of diphenyl telluride in transition metal carbonyl chemistry has also been well illustrated during studies of manganese and rhenium compounds. 

The vast majority of tris(pyrazolyl)borate ruthenium complexes prepared until now contains the parent Tp ligand. In contrast to other transition metals, ruthenium compounds which bear bulky Tp ligands remain still rare and are, thus far, limited to Tp, Tp Tp and Tp as shown in Chart 1. 

Polypyridyl transition metal complexes, especially those of ruthenium(II), have been extensively apphed in light harvesting and information storage, because they exhibit a wide range of photophysical and electrochemical properties. Storrier et al. have reported the synthesis and characterization of PAMAM dendrimers functionalized with tris(bipyridyl) ruthenium(II) (dend- -[Ru(bpy)3] +) or bis (terpyridyl) ruthe-nium(II) (dend-n-[Ru(tpy)2] ) complexes (GO, 1, 2, 3, and 4 with 4, 8, 16, 32,... 

There are many examples of polymers containing transition metals coordinated to bipyridine and related ligands (150-164). The luminescent properties of tris(bipyridine)ruthenium(II) complexes have generated a great deal of interest in these materials (152-158). Polymers containing metal ions coordinated to three bipyridine or substituted pyridines can contain the metal as an integral part of the polymer skeleton (66) (165-168), pendent to the polymer backbone (67) (154 156), or in a group pendent to the polymer backbone (68) (157,158). 

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