Chain Cluster

Fig. 5.17 View of the structure of the orthorhombic mixed-halide cluster phase Cs2[ Zr6B)CbT.98l3.02] showing the two types of cluster chains (thermal ellipsoids with 50% probability). Cs cations and inner halides are omitted for clarity.

Hughbanks T, Hoffmann R (1983) Molybdenum chalcogenides Clusters, chains, and extended solids. The approach to bonding in three dimensions. J Am Chem Soc 105 1150-1162... 

Figure 3. A view of one MohO% cluster chain in Ba1.HMos016 which shows intrachain Mo-Mo and Mo-O bonding. ( See Table III for atom numbering scheme.)...

Figure 7 Metal cluster chain in Zr5Te4. Only Zr atoms are shown...

The effect of the ion on the strength of the hydrogen bond between water molecules dies off rapidly in the outer shells of the clusters. Almost the same values are observed in the third solvation layer and in tetrahedral water clusters. Chain structures discussed by Burton and Daly 220> show an analogous behavior (Table 19). 

There are several interesting families of inorganic mixed-valence compounds that we have not discussed here (see Yvon, 1979 McCarley, 1982). For example, there are metal-cluster compounds such as the Chevrel phases, M,jMo6X8(X = S or Se) and condensed metal-cluster chain compounds such as TlMojScj, TijTe, NaMo O and M PtjO. TTF halides and TTF-TCNQ complexes (Section 1.9) constitute molecular mixed-valent systems in which the mixed valency is associated with an entire molecule the charge on TTF in such compounds is nonintegral. The structure of TTF-Br(, 79 and... 

Well preserved specimens show structural details in their cell wall and sheath. Others are present in typical stages of reproduction or growth. Individuals are united in clusters, chains, ramifications or other definable arrangements. 

Stoll and Preuss (50) have examined Li clusters using a SCF-MO calculational procedure. Although they found convergence problems for the large clusters, chains were more stable than layer structures or three-dimensional crystal structures for the smaller clusters, and BE In is an increasing function of size. The width of the occupied part of the conduction band was in the order 3d>2d> 1 d, as described for silver clusters. The lowest state in the conduction band also drops in energy with increasing size. The calculated work function is within 10% of the experimental bulk work function. 

A final three dimensional perspective of the structure is provided in Fig. 6. From this view it is readily discerned that the Na ions are stacked along the c-axis in tunnels created by crosslinking of the metal oxide cluster chains. Each Na ion occupies a site of tetragonal coordination symmetry surrounded by eight 0 atoms at a distance of 2.740(8). When these structural features are ta en into consideration the formula NaMo O may be rewritten as Na [(Mo Mo /2°8/202/2 02/2 t0 reflect th connectivity relations witnin and between the chains. 

Figure 5. Mo 06 cluster chain viewed perpendicular to the chain direction ((0)...

In addition to simple metal nodes, TPyP MOFs also were prepared that utUize compound nodes, for example, dicopper(II) tetraacetate, Cu2(AcO)4 (123), and CU2M03O11 extended cluster chains (119). The Cu2(AcO)4 forms paddlewheels similar to the Rh + paddlewheels mentioned in the discussion of TCPP MOFs above. However, unlike the aforementioned MOFs, TPyP MOFs interact via axial ligation of the pyridyl nitrogen atoms to the preformed Cu2(AcO)4 dimers. In Cu2(AcO)4[Cu(TPyP)] MOF (123), the Cu paddlewheels thus act as two... 

Handschuh, H. Gantefor, G. Kessler, B. Bechthold, P.S. Eberhardt, W. Stable configurations of carbon clusters chains, rings, and fullerenes. Phys. Rev. Lett. 1995, 74(7), 1095-1098. 

It should be noted that each B-type atom coordinates 1,2 and 3 cluster chains there is no isolated Cs atom in this matrix of Cs atoms. As will be pointed out later, the principal features of the characteristic environment of the CS11O3 cluster in CS7O are found in every compound containing this cluster in spite of different stoichiometries and cluster arrangements. 

T. S. Zwier, The Infrared spectroscopy of hydrogen-bonded clusters chains, cycles, cubes, and three-dimensional networks, In Advances in Molecular Vibrations and Collision Dynamics, edited by J. M. Bowman (JAI, Greenwich, 1998), pp. 249-280. 

Figure 22 Structure of a condensed cluster chain in Gd2Cl3...

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