Platinum, luminescence

Emission spectra have been recorded for four aryl-substituted isoindoles rmder conditions of electrochemical stimulation. Electrochemiluminescence, which was easily visible in daylight, was measured at a concentration of 2-10 mM of emitter in V jV-dimethylformamide with platinum electrodes. Emission spectra due to electrochemi-luminescence and to fluorescence were found to be identical, and quantum yields for fluorescence were obtained by irradiation with a calibrated Hght source. Values are given in Table X. As with peak potentials determined by cyclic voltammetry, the results of luminescence studies are interpreted in terms of radical ion intermediates. ... 

Note that a similar situation arises in the study of heterogeneous deactivation of electron-excited molecules of N2. Thus, an opinion expressed by Clark et al. [152] states that the coefficients of heterogeneous deactivation of N2(A S, v = 0.1) for all surfaces are close to unity. On the other hand, Vidaud with his coworkers [59, 153] have obtained 3 10 2 and (1.8 + 1.2) 10 values for these coefficients shown by platinum and Pyrex, respectively. Tabachnik and Shub [154] investigated heterogeneous decay of NaC A SJJ ) molecules on a quartz surface by the method of bulk-luminescence spectroscopy. The authors carried out a series of experiments within a broad (about four orders of magnitude) range of active particle concentrations and arrived at a conclusion that at a concentration of N2( A 2 ) in excess of 10 mole/cm , the... 

Both chloro ligands of [Pt2Cl2(/u-dppm)2] are replaced by quinoline, 1-methylimidazole, and 4-t-butylpyridine, but only one is replaced by 2,4,6-trimethylpyridine.109 All of these platinum(I) dimers and pt2(PPh3)2(/i-dppm)2] display solid-state luminescence at room temperature and long emission lifetimes at 77 K.109... 

The luminescent, dinuclear platinum(II) species [Pt2(/x-S)2(dppy)4] (134) can be prepared by treating [PtCl2(dppy)2] with NaSH in the presence of NEt3 under anaerobic conditions.331 When the complex is dissolved in CH2C12 solution, pale-yellow crystals of [Pt(S2CH2)(dppy)2] (135) are formed, the first example of a four-membered, saturated dithiolato platinacycle. 

Optical sensors for oxygen are among the few sensors, which have found practical application for process-monitoring and clinical diagnostics. They are generally based on compounds such as platinum porphyrins or ruthenium phenanthroline derivatives (Table 17) which show a decrease in luminescence upon exposure to molecular oxygen15. 

The aim of this chapter is to review the chemistry of chalcogenolates in the last 10 years. The more recent reviews in this field included chalcogenolates of the s-block elements,13,14 early transition metal thiolates,15 metal complexes with selenolate and tellurolate ligands,16 copper(I), lithium and magnesium thiolates,17 functionalized thiolate complexes,18 19 pentafluorobenzenethiolate platinum group compounds,20 tellurium derivatives,21 luminescent gold compounds,22 and complexes with lanthanide or actinide.23... 

Luminescent Platinum Compounds From Molecules to OLEDs... 

Until relatively recently, most work focused on organic luminophores as sensor-probe materials. However, luminescent transition metal complexes, especially those with platinum metals (Ru(II), Os(II), Re(I), Rh(III), and Ir(III)) have shown considerable promise and are receiving increasing attention. More recently Pt(II) complex have shown promising results.(4) Many of these materials have highly desirable features ... 

Platinum and palladium porphyrins in silicon rubber resins are typical oxygen sensors and carriers, respectively. An analysis of the characteristics of these types of polymer films to sense oxygen is given in Ref. 34. For the sake of simplicity the luminescence decay of most phosphorescence sensors may be fitted to a double exponential function. The first component gives the excited state lifetime of the sensor phosphorescence while the second component, with a zero lifetime, yields the excitation backscatter seen by the detector. The excitation backscatter is usually about three orders of magnitude more intense in small optical fibers (100 than the sensor luminescence. The use of interference filters reduce the excitation substantially but does not eliminate it. The sine and cosine Fourier transforms of/(f) yield the following results ... 

Using benzimidazole (BzimH) as the non-linear bridging motif, luminescent platinum(II) trimeric systems [Pt(thpy)(Bzim)]3 (92) and [Pt(bzqn)(bzim)]3 (93) have been synthesized from sodium benzimidazolate and luminescent... 

Some electrochemically active substances that can generate photons on an electrode surface are suitable labels for homogeneous immunoassays. A labelled antigen exhibits an electrochemical reactivity and produces luminescence, but when it is immunochemically complexed, the labelled antigen loses its electrochemiluminescent properties. One optical immunosensor for homogeneous immunoassays was assembled by spattering platinum on the end surface of an optical fibre. Spattered platinum maintains optical transparency and functions as an electrode. An optical electrode efficiently... 

Yam VW-W, Chan KH-Y, Wong KM-C, Chu BW-K. Luminescent dinuclear platinum(II) ter-pyridine complexes with a flexible bridge and sticky ends. Angew Chem Int Ed 2006 45 6169-6173. 

The complex was non-luminescent at room temperature, but it displayed luminescence in the solid state at 77 K, showing an unstructured emission at 443 nm. This emission was attributed to the gold centers or to the interaction between the gold and platinum ions. In fact, the isostructural [(NH3)4Pt][Ag(CN)2]1.4(H20) was not luminescent and, similarly, the corresponding [Ni(NH3)2][Au(CN)2]2, whose structure only showed gold-gold interactions (3.0830(5) A), did not display luminescence at either room temperature or at 77 K. 

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