CLUSTERS salts

The exceptional renewed interest in supported gold catalysts leads us to mention here a few recent examples of the formation of in situ gold carbonyl species from supported gold that can be related to the preparation of supported Au nanoclusters [53-55]. On the other hand, bimetallic carbonyl cluster salts of [Au4Fe4(CO)i,5] and [AuFe4(CO)i,5] have been used recently in the preparation of Au/Fe0,t/Ti02 catalysts for the total oxidation of dichlorobenzene and toluene [56]. 

A homonuclear gold cluster has been used as a precursor to a heteronuclear species in which two gold atoms are bonded to Co(CO)4 fragments [Eq. (55)] (90). Treatment of the cluster salt K[Co3Fe(CO)12] with [Bu"N][AuI2] also affords a mixed-metal cluster containing a Au Co-(CO)4 unit [Eq. (56)] (91). 

IMS-MS applications published in the literature can be grouped into two categories. The first contains studies of conformations of flexible molecules. Such flexible molecules include synthetic polymers and biopolymers such as peptides, proteins, and oligonucleotides. The studies of the second category deal with the geometry of cluster ions such as carbon clusters, semiconductor clusters, metal clusters, salt clusters, ion-ligand clusters. The major conclusions regarding structure of these systems are reviewed in Sect. 5. 

Mixed Salts, or Cluster, Salt Dose rate ( kGy h ) Irradiation source Particle structure (Ref.)... 

The dimer 12 can only be dissolved in ether solvents, when it undergoes dissociation, as corroborated by cryoscopic measurements and Na NMR spectra 24). In contrast, the Na4-cluster salt 14 cannot be dissolved in any common organic solvents without decomposition... 

These solids can be considered as end-members of microporous solids families, just as in the case of the sodalite. The solid state synthesis of more opot and microporous members is essentially a problem of template selection (metallic clusters, salts of voluminous cations and/or anions ). This template should be able to stracture the microporous space, and therefore lead to a sufficient chemical and thermal stability under the syndesis conditions. 

Other organic redox shuttles based on aromatic compoimds with heteroatom substitutions include phenothiazine [18], triphenylamine [89], diarylamines with different substitutions [38], and 2-(pentafluorophenyl)-tetrafluoro-l,3,2-benzodi-oxaborole [29, 137]. Nitroxide radicals such as (2,2,6,6-Tetramethylpiperidin-l-yl) oxy (TEMPO) have been studied as a redox shuttle as well but showed inferior rate of charge transfer compared with DDB [90]. In addition, lithium borate cluster salts (Li2Bi2Fi2) have also been reported to be suitable redox shuttle additives for 4-V lithium ion chemistry (Chen et al. [26]). 

Chen Z, Liu J, Jansen AN, GtrishKumar G, Casteel B, Amine K (2010) Lithium borate cluster salts as redox shuttles for overcharge protection of lithium-ion cells. Electrochem Solid-State Lett 13 A39-A42. doi 10.1149/1.3299251... 

The imidazolium/boron cluster salts can be separated into two groups the first one inclndes the monovalent anions. These compounds exhibit low melting points, around or below lOO C and no thermotropic metaphases. The imidazolium salts of cobaltabis(dicarbollide) with 4,6,8,10,12, and 14 carbon atoms in the side chain of the imidazolium cation are liquid at room temperature. 

---