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Dianionic clusters

Salt elimination reactions proved to be very effective for the synthesis of closo-heteroborates with the heavy elements of this group. Todd and co-workers prepared for the first time the lead, tin and germanium cluster dianions [EBnHn]2 as shown in Scheme 3.3-5 [17]. [Pg.313]

Two M(PR3) groups can be introduced into a preformed cluster dianion. Equation (6) shows an example (27). [Pg.251]

In 1980, Albano et al. (32) showed that two Cu(NCMe) units could be incorporated into a mixed-metal cluster by treating a preformed cluster dianion with the complex [Cu(NCMe)4][BF4] ]Eq. (16)]. Other workers... [Pg.253]

C. Femoni, F. Kaswalder, M. C. Iapalucci, G. Longoni, and S. Zacchini, Infinite Molecular [Pt3n(CO)6n]2 Joo Conductor Wires by Self-Assembly of [Pt3n(CO)gn]2 (n = 5-8) Cluster Dianions Formally Resembling CO-Sheathed Three-Platinum Cables, Eur. J. Inorg. Chem. 2007, 1483-1486. [Pg.126]

Lawrence F. Dahl Platinum carbonyl cluster dianions ( tinker toy construction) with trigonal prismatic configuration... [Pg.898]

Salts of the cluster dianion with other cations may be isolated by use of the appropriate water soluble salt in place of Et4NBr. [Pg.184]

Figure 104 shows the molecular structure of the dicarbide cluster dianion [Co6Ni2(CO)16(C)2]2- [183]. [Pg.197]

Some uncertainty still exists on the exact formulation and structure of a series of redox-active giant heteronuclear clusters formulable as Os20M and/or Os18M3 (M = Hg, Au, Ag). Accordingly, the previously formulated cluster dianion [Os20Hg(C)2(CO)48]2 [195] has been now reassigned as... [Pg.208]

Yannouleas and Landman have theoretically considered the stability and decay channels of Au and Ag . They find that autodetachment dominates fission as the mode of decay at a finite temperature. Earlier they had studied sodium cluster dianions. These calculations show pronounced shell-effects in the second electron affinities illustrating the failure of the simple electrostatic model of charging a conducting sphere as depicted in Figure 1. However, the Coulomb barrier calculated with such simple assumptions probably is a reasonably good approximation. The importance of the Coulomb barrier in multiply charged anions is emphasized below. [Pg.298]

The bicapped octahedral octanuclear osmium cluster dianion [Osg(CO)22] can be prepared from the solid state pyrolysis of [Os3(CO)io(NCMe)2]. An X-ray analysis of the [N(PPh3)2j salt shows that the two Os(CO)3 caps occupy the 1 and 3 faces of the octahedron s as shown in Fig. 10, and the structure of the dianion is consistent with the electron count of 110 e and seven skeletal electron pairs. [Pg.457]

The cluster dianions [Co8C(CO)ig]- (Fig. 8a) and [NigC(CO)i6] provide rare examples of a first-row main-group atom occupying a square antiprismatic cluster cavity,and also illustrate the capacity of carbon to become eight-coordinate. However, on progressing to the heavier main-group elements such as Si, P, S and As we find a propensity for clusters based on the square-antiprism. [Pg.890]

The use of singly charged cations, i.e. [Ru(C5H5)(CH3CN)3]+, in reactions with cluster dianions, allows for the introduction of two organometallic units... [Pg.1780]

Synthesis and structural characterization of Pt carbonyl clusters dianions... [Pg.222]

The tetranuclear cluster dianion [H2Ru4(CO)i2] has been reported to show excellent activity for the reduction of nitrobenzene to aniline by CO/H2 (120 °C, 20 Kg/cm (H2/CO = 19 1), in methanol) [41]. The IR spectrum of the catalytic solution at the end of the reactions showed the presence of the dianion. The clusters [HRu3(CO)h] and [H3Ru4(CO)i2] proved to be less effective [41]. Note that the very low CO pressure ( 1 atm) may avoid cluster decomposition to yield monomeric complexes. [Pg.145]

The face-capped octahedral cluster dianion [Os7(CO)2o] 290 forms in 70% yield from the reduction of Os7(CO)2i with Addition of Os(CNBu )(CO)4 to Os6(CO)is/Me3NO affords Os7(CO)2o(CNBu ) 291 in 25% yield. ... [Pg.1030]

Osmium cluster dianions [Os]7(CO)36] 330 and [Os2o(CO)4o] 331 are formed in up to 10 and 20% yields, respectively, by vacuum pyrolysis of Os3(CO)io(NCMe)2 at temperatures above 260 °C. Complex 330 contains a close-packed arrangement of 16 metal atoms, with the additional Os breaking the otherwise threefold symmetry of the metal core. The two osmium atoms with metal connectivities of 8 and 9 have significantly shorter Os-Os bond distances (2.663 A), comparable to that of the bulk metal (2.6754A). The cluster is electron-precise, with 210 c.v.e. The electron-deficient complex 331 consists of a cubic close-packed arrangement of metal atoms, and has been characterized by IR spectroscopy in five oxidation states. [Pg.1039]


See other pages where Dianionic clusters is mentioned: [Pg.246]    [Pg.283]    [Pg.795]    [Pg.344]    [Pg.267]    [Pg.199]    [Pg.109]    [Pg.125]    [Pg.387]    [Pg.390]    [Pg.179]    [Pg.119]    [Pg.283]    [Pg.298]    [Pg.301]    [Pg.453]    [Pg.469]    [Pg.1296]    [Pg.119]    [Pg.67]    [Pg.332]    [Pg.355]    [Pg.178]    [Pg.92]    [Pg.151]    [Pg.19]    [Pg.1035]    [Pg.1036]    [Pg.1036]    [Pg.151]   
See also in sourсe #XX -- [ Pg.7 , Pg.8 ]




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Carbon cluster dianions

Dianionic clusters electronic properties

Osmium carbonyl clusters dianion

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