Osmium metal arrangement

A knowledge of these enthalpic terms, and therefore of the relative bond energies, would be expected to considerably clarify many of these fundamental aspects. The data in Table 4 show that, with the main exception of rhenium and osmium, the metal-metal distances in the tetranuclear clusters and in the pure metals are quite similar this relationship is generally valid for all the polynuclear carbonyls60. The metal-metal bond energies in clusters are therefore expected to be of the same order as those in the metallic state for a close-packed arrangement, these are given by the formula Z m-m = A//f M(g)/6. 

Ru3(CO)i2] and 7,8-Me2-Kfframework bridges a triangular arrangement of ruthenium or osmium atoms with the open CBBBlf or CCBBB faces, respectively, coordinated in a pentahapto fashion to one metal atom while the carborane cage forms two exo-polyhedral B-H M bonds with the other two metal atoms. 

Table 4 lists the densities of a variety of substances. Osmium, a bluish white metal, is the densest substance known. A piece of osmium the size of a football would be too heavy to lift. Whether a solid will float or sink in a liquid depends on the relative densities of the solid and the liquid. Figure 11 shows several things arranged according to densities, with the most dense on the bottom. 

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