Metal carbonyls luminescence

With respect to CO complexes, the luminescence spectra of a series of Group VI metal carbonyls and substituted carbonyls were obtained in frozen gas matrices at 12K. In addition, the IR spectra of HCo(CO>4 and HCo(CO)3 (proposed as an intermediate in hydroformylation) were observed in an argon matrix. ... 

Abstract This work describes the ultrafast processes preceding the photoinduced decarbonylation of the simple metal carbonyl complexes Cr(CO)6, Fe(CO)5, and Ni(CO)4. Models for their electronic structure are presented based on recent ab initio quantum chemical calculations and these models are used to describe initial excited-state dynamics leading to the expulsion of one CO ligand. Experimental support for the proposed excited-state dynamics is presented, as obtained from ultrafast pump-probe experiments using mass-selective detection, ultrafast electron diffraction, and luminescence studies. The results of some steady-state experiments are also presented where they support the proposed dynamic model. 

The most remarkable aspect of the ClRe(cO) X systems is that their luminescence is fairly Intense even xn room temperature fluid solutions (Table 12). These are the first examples of metal carbonyl complexes known to luminesce under these conditions. Since such systems are extremely useful in the study of intermolecular as well as Intramolecular relaxation of excited state complexes, their discovery is very significant. The similarly luminescent and photostable ionic complex, Ru(bipy)3, has been used extensively in such studies (204). 

Figure 4. Correlation of log Kq and E (metal carbonyl) for quenching of (Uol ) luminescence by the carbonyls in Table 5. (A) and (B) refer...

The absorption spectra [8] and luminescence spectra [9] of metal carbonyls have been reviewed and the intent of the present discussion is to provide a brief overview of the spectral properties of this type of complex. Because of the relative high energies of the n orbitals of the coordinated carbonyls, the lowest energy electronic transitions of the mononuclear carbonyls M(CO)y are generally ligand field (LF, i.e., d-d) in character. This is illustrated with... 

The photochemistry of rhenium complexes occupies a prominent position in the photochemistry of transition metal complexes. Along with early preparative studies on photosubstitution of carbonyl species like Re(CO)sX, the preparation of the remarkably stable yellow complex /ac-Re(CO)3(phen)Cl foreshadowed the discovery of the a large class of related luminescent materials by Wrighton and co-workers in the 1970s [ 1 ]. As pointed out by Vogler and Kunkley, the current photochemistry of rhenium complexes is rich, spanning eight oxidation states from formal Re(0) (for example, Re2(CO)io) to formal Re(VII) (for example MeReOs) [2],... 

A complementary application to the use of Os complexes in photovoltaic cells is the use of luminescent Os complexes in electroluminescent devices. There has been a significant amount of work in this area, particularly as it applies to the development of Os complexes with high quantum yields for phosphorescence. A review of transition metal complexes used in OLED development was published in 2006 by Evans et al. [126]. Another very recent review discusses various Os(II) carbonyl complexes with diketonate, hydroxyquinolate, bipyridine, and phenanthroline ligands as emitters in OLED devices [127]. A few select examples of Os complexes in OLEDs are presented here. 

Unlike most metal complexes containing the fa c-(diim i n c) Re1 (CO). unit, which are typically highly luminescent in solution, trinuclear rhenium carbonyl compounds 7 and 8 (see Fig. 11a) show only weak luminescence ( em = 0.0015) in CH3CN at room temperature [36], The quenching appears to occur via intramolecular... 

Carbene Complexes Carbonyl Complexes ofthe Transition Metals Cyanide Complexes of the Transition Metals Dinuclear Organometallic Cluster Complexes Electron Transfer in Coordination Compounds Electron Transfer Reactions Theory Electronic Structure of Organometallic Compounds Luminescence Nucleic Acid-Metal Ion Interactions Photochemistry of Transition Metal Complexes Photochemistry of Transition Metal Complexes Theory Polynuclear Organometallic Cluster Complexes. 

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