Applications mixed ligands

The application of Mossbauer spectroscopy in the study of mixed ligand complexes. K. Burger, Inorg. Chim. Acta, Rev., 1972, 6, 31-46 (125). 

In nonbiological applications, mixed ruthenium complexes of bipyridyl ligands and substituted pteridine diones have been used as components of photovoltaic cells <2002JPH167>. When fabricated into sol-gel processed titanium oxide electrodes, these complexes achieved photocurrent conversion efficiency in the range 20 8%. 

The products of partial substitution for the OR-groups, i.e., alkoxocarbox-ylates, P-diketonates M(OR)mX , where X= RCOO, acac, thd, etc.—the mixed-ligand complexes—usually are more soluble and stable than M(OR) , as their molecules contain the chelate cycles. Mehrotra et al. [223] have described a great number of such products (usually liquid or amorphous), in which individuality appeared sometimes questionable. During recent years, however, in connection with the application of these compounds to the synthesis of oxides, interest in them has increased, and a number of them have been isolated and structurally characterized (Chapter 7). Unfortunately, length restriction did not permit us to present a complete review of their chemistry in this book. 

With rich luminescent properties, long-lived CT excited states and a variety of bimolecular photochemical reaction pathways, the mixed-ligand square-planar diimine dithiolene complexes of d8 metal ions show great promise for solar-energy conversion, as luminescent probes or in photocatalytic applications. Complexes of this type have also received attention for the nonlinear optical properties, such as second harmonic generation, related to the MMLL CT excited state (14, 129). 

This chapter focuses on recent results concerning the class of square-planar rf metal-bis(dithiolene) or mixed ligand complexes, discussing their properties and applications as building blocks of molecular materials where the bulk properties are based on their component molecules interacting with each other at the supramolecular level. 

We have noticed a correlation between the logarithm of the selfexchange rate constant for a series of [CoNe] couples and the degree of substitution at the coordinated amines as judged by the number of amine protons in the complex (Fig. 12). It should be noted that more than half the points that fall on the line have been estimated by application of the cross relationship to the rate of a single cross reaction with (102). Not all the points in the plot are homoleptic complexes some mixed ligand CoNe complexes were included because of the need to try to verify the unexpected observation. The line in Fig. 12 was... 

Progress in the application of Arsenazo 111 reagent in analytical chemistry has recently been discussed [1]. A review of systems based on ternary and multicomponent complexes recently developed for spectrophotometric determination of elements have been presented [2]. The use of mixed ligand, surfactant sensitized, ion-association, flotation, derivative and FIA techniques has been discussed. 

Kanellakopulos et al. have demonstrated the wide applicability of the protic acid NHi for the elegant preparation of many mixed-ligand metal cyclopentadienides of f-block and main group elements (14) ... 

Treatment of 3-borolenes or 2-boraindans with bulky lithium amides yields the dilithiated aromatic borolide dianions, which are applicable as ligand precursors for transition-metal complexes. Many borole complexes including a number of unusual multidecker sandwich complexes and mixed-metal clusters have been described. 

In the 1960 s, when new methods for the preparation of complexes and spectroscopic methods for their physicochemical studies were concurrently progressing, coordination chemists noted applications of chromatographic techniques to the preparative studies of mixed ligand complexes. Ion-exchange column techniques, in particular, were most rapidly developed for the preparative studies. 

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