Luminescent complexes

The compounds are luminescent at room temperature with structured emission profiles that suggest aryl ligand-centered emission. Time-dependent density-functional theory calculations support this assignment. Xantphos and related ligands are not spectroscopically innocent the LUMOs of these compounds reside mostly on the connecting pillars and not on gold or the o-aryl ligands. 

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The high luminescent complex [Au2 (PPh2)2-CH2 ](OTf)2 with a triplet excited state can be used in light-emitting diodes.2619... 

Marcantoncetos et al. [112] have described a phosphorimetric method for the determination of traces of boron in seawater. This method is based on the observation that in the glass formed by ethyl ether containing 8% of sulfuric acid at 77 K, boric acid gives luminescent complexes with dibenzoylmethane. A 0.5 ml sample is diluted with 10 ml 96% sulfuric acid, and to 0.05-0.3 ml of this solution 0.1ml 0.04 M dibenzoylmethane in 96% sulfuric acid is added. The solution is diluted to 0.4 ml with 96% sulfuric acid, heated at 70 °C for 1 h, cooled, ethyl ether added in small portions to give a total volume of 5 ml, and the emission measured at 77 K at 508 nm, with excitation at 402 nm. At the level of 22 ng boron per ml, hundredfold excesses of 33 ionic species give errors of less than 10%. However, tungsten and molybdenum both interfere. 

Complexes M(CH2C CC=CMe)(CO)nCp [325 M = Mo, n = 3 M = Fe, = 2 (Scheme 74)] were obtained from the carbonyl anions and l-chlorohexa-2,4-diyne. Subsequent chemistry involves protonation (HBF4) to cationic allene or diene complexes, or addition of MeOH to give allylic derivatives, which are formed with concomitant insertion of CO. The latter can also be obtained from the cationic species and NaOMe. The allene-iron cation reacts with NHEt2 to form an ynenyl complex. The luminescent complex Re(CO)3(5,5 -Bu 2-bpy) 2 (At-C=CC6H4C CC=CC6H4C=C) has been reported. ... 

Faulkner, S. Matthews, J. L. Fluorescent and Luminescent Complexes for Biomedical Applications, Comprehensive Coordination Chemistry II , Vol. 9 Eds. McCleverty, J. Meyer, T. J. Pergamon, 2003, p. in press, in press. 

Like the d3 Cr(III) systems much spectroscopic work has been carried out on six-coordinate low-spin d6 complexes, and it can now be said that the essential features of the LF spectra are understood.3,30 42) However, unlike the Cr(III) systems, the low-spin d6 systems are not well understood with respect to their luminescense phenomena. This is due, in part at least, to the diversity of luminescent complexes... 

Fluorescence quenching is another technique also using energy transfer, but in this technique, the acceptor is a quencher which absorbs energy from the donor but does not emit light, instead the quencher dissipate the energy as heat. Therefore when the donor and the quencher are in close proximity, the fluorescence of the donor is not observed. For this purpose, several typical quenchers are available, whose structures are shown in scheme 14. These quenchers are effective both for organic and lanthanide luminescent complexes. 

Hydroxyanthraquinone derivatives, especially alizarine red S (fig. 67), also form 1 1 complexes with Ybm ions (Korovin et al., 1988). The observed lifetimes are very short, around 0.3 ps, but comparable to those listed in table 15 for the complexes with triphenylmethane dyes. The relative luminescence intensities of Ybm complexes with several different dyes are summarized in fig. 68. The intensities are given relative to the more luminescent complex, with phthalexon S. It is noteworthy that all these complexes have absorption maxima at wavelengths longer than 500 nm, between 505 nm for thorin I and 590 nm for methylthymol blue H475d, and can thus be excited by the 546 nm-emission line of a mercury lamp. 

Zubieta, Valliant and co-workers recently reported the synthesis of an amino acid containing a (quinoline-CH2)2-NR chelate that can react with [Re(CO)3Br3]2 to form a luminescent complex (20) [56]. This complex shows dual emission at 425 and 580 nm with a lifetime of ca. 4.3 to 9.8 ps in various solvents. The presence of an amino acid in this complex enables its incorporation into a peptide using a conventional automated synthesiser. A short peptide fMLF has been labelled with this luminescent complex and the conjugate has been used to probe the biological target human FPR studied by flow... 

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