Hexanuclear systems

In the case of the other two complexes, two trinuclear molecules interact through the gold atoms forming hexanuclear systems. These prismatic [Au3(MeN = COEt)3]2 units have intermolecular distances of 3.2328(10)—3.3545(10) A, in the adduct with... 

Apart from the gold(i) system, bis(mesityl)mercury(ii), which also possesses a heavy metal center with strong relativistic effects, has been used for the synthesis of the mixed metal silver(i) aryl complexes, [HgAg2(mes)X2]2 (X = OTf 13a (Figure 7), C104 13b).33 X-ray crystal structure analysis of 13a revealed its hexanuclear nature with the... 

Tetranuclear 77-79 and hexanuclear 80 systems, in their X-ray structures, show respective 1,3 and 1,3,5 alternate arrangements and the latter was folded because of the hydrophobic interactions between methyl protons and 2-dmpymo... 

The electrochemical reduction of TiCU and ZrCl4, in chloroaluminate melts and other molten salt systems, to lower valent halides has been fairly widely studied [4-7]. This has also been extended to studies of centered hexanuclear Zr halide clusters. Thus, ambient temperature AICI3 -1 -ethyl-3-methylimidazolium chloride (ImCl) molten salts, both basic (40/60 mol% AlCls/ImCl) and acidic (60/40 mol% AICI3 /ImCl), were used in an electrochemical investigation of clusters... 

Heteropoly anions. 760-764 Hexagonal crystal system, 75. 78 Hexanuclear dusters. 816 VtexgonsA closest packed (hep)... 

These kinds of species are of considerable bioinorganic and catalytic interest.25 Complexes with central FerS4, units could be obtained, such as the remarkable linear [Fe2S2(WS4)2]4 (18)17 and the hexanuclear [Fe3S2(WS4)3]4 (19)21 with an almost planar array of six metal atoms. It is also worth noting that four other complexes could be isolated from the system Fe"/WS4 /solvent (see Section 16.3.2.2.1). 

When triethanolamine H3L13 (35) was reacted with sodium hydride and iron(III) chloride, the hexanuclear centrosymmetric ferric wheel [Nac Fe6(L13)6 )Cl (36) was isolated. Amidst a set of possibilities in the template-mediated self-assembly of a supramolecular system, the one combination of building blocks is realized that leads to the best receptor for the substrate [112]. Therefore, the six-membered cyclic structure 36 is exclusively selected from all the possible iron triethoxyamine oligomers, when sodium ions are present. The iron(III) complex 36 is present as an Sg-symmetric wheel, with an encapsulated sodium ion in the center and a chloride counterion. Consequently, the trianion (L13)3- acts as a tripodal, tetradentate, tetratopic ligand, which each links three iron(III) ions and one sodium ion. In the presence of cations with different ionic radii, different structures are expected. Therefore, when triethanolamine H3L13 (35) was reacted with cesium carbonate and iron(III) chloride, the octanuclear centrosymmetric ferric wheel [Csc Fe8(L13)8 ]Cl (37) was isolated (Scheme 13) [113]. 

J. C. Calabrese, L. F. Dahl, A. Cavalieri, P. Chini, G. Longoni, and S. Martinengo, Synthesis and Structure of a Hexanuclear Nickel Carbonyl Dianion, [Ni3(CO)3( j,2-CO)3]22, and Comparison with the [Pt3(CO)3(p2-CO)3]22 Dianion. An Unprecedented Case of a Metal Cluster System Possessing Different Metal Architectures for Congener Transition Metals, J. Am. Chem. Soc. 96, 2616-2618 (1974). 

For the mononuclear and dinuclear compounds, except V(CO)6, the mnnber of valence electrons per metal atom is 18. The EAN (effective atomic number) of the metal is the number of electrons of the d" configuration added to twice the number of CO groups, one electron being further added in the case of metal-metal bonded dinuclear systems. For trinuclear, tetranuclear, and hexanuclear compoimds (metal-carbonyl clusters), the cluster valence electron counting is 48, 60, and 86, respectively. As the [K(cryptand 2.2.2)] derivative. As the tetraalkylammonium derivative. As the tetrachloroaluminate. 

Heteropoly anions, 760-764 Hexagonal crystal system, 75, 78 Hexanuclear clusters, 816 Hexgonal closest packed (hep) system, 120 Hieber, Walter, 643 Highest occupied molecular orbital (HOMO). 351, 428, 721, 722... 

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