Intermetallic bond

In a study of the hydrolysis of platinum(II)-nitrile complexes to afford the corresponding amides, the first well-characterized examples of platinum(II) complexes that dimerize spontaneously to form weakly bonded Pt-Pt dimers with an unsupported intermetallic bond have been described.166 For example, treatment of cw-[PtCl2(NCBut)2] with excess KOH affords the amide species cw-[PtCl2 HN=C(OH)But 2], which exists as a dimer (49) both in solution and in the solid state, with a Pt-Pt bond length of 3.165(1) A, as determined by X-ray crystallography. Four... 

A novel binuclear Ptu-Ptn complex Ba2[Pt2(C404)4] 6H20 can be prepared from Pt(H20)4+ and squaric acid. The tetrakis-bridged fi-0, squarato complex has a Pt-Pt separation of 3.061 A, indicative of negligible intermetallic bonding.1640... 

Finally, the photolytic cleavage of the intermetallic bond in a Ptm species unsupported by covalent bridges, can lead to formation of highly reactive 17-electron metal-centered radicals which can also activate C-M and C-X bonds [14]. 

Another interesting feature of the dinuclear iridium complex [IrCl(PF3)2]2 is its very dark color and metallic luster in the solid state, indicative of intermetallic bonding. A recent single-crystal structure determination (149) reveals that the structure consists of infinite zigzag chains of iridium atoms with short inter- and intramolecular Ir Ir contacts (see Figs. 15 and 16). 

Reaction of NaBH4 with the iron complex 486 (L = phosphine ligand) leads to C—C and Fe—Fe bond formation to give compound 487. Oxidative cleavage of the intermetallic bond produces a complex (488) containing a tetrathiooxalate ligand. Sodium amalgam yields 488 directly. When L... 

Tin complexes (R2Sn)3 have been less studied than their germanium counterparts but are no less readily prepared. The reaction of (2,6-Et2C6H3)2SnCl2 with lithium naphthalenide gives (R2Sn)3 with intermetallic bond lengths of 2.854-2.870 A. ... 

A number of models have been proposed to explain the mechanism of this phenomenon, which include formation of intermetallic bonds with localized charge... 

The evidence also indicates that the deuteration of benzene differs markedly from the deuteration of aliphatic olefines in that very little redistribution occurs and that the process seems to be limited to the addition of deuterium without additional exchange. Furthermore, the order of activities of different metals for the deuteration of benzene is quite unlike the order for the hydrogenation of ethylene and bears no relationship to the percentage d-bond character of the intermetallic bonds. 

This type of interfacial layer is characterized by a constant chemical composition across several lattice distances. The formation of the interface layer results from the chemical reactions of film atoms with substrate atoms which may also be influenced by the residual gas. A distinction has to be made between intermetallic bonds and alloys and chemical bonds such as oxides, nitrides etc. 

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