Polynuclear chains with direct interactions between heavy atoms

4 Polynuclear chains with direct interactions between heavy atoms 

The same compound has a crystalline yellow modification of known structure in which the molecules are packed so that Au atoms are positioned far from each other. The RDF of the polycrystalline powder of this phase is shown in Fig. 9b. It contains no strong peaks near 3 A typical of Au-Au bonds. Comparison of two curves confirms the above interpretation of the strong peaks in the lower curve experimentally. This is a curious example in which the metal-metal interactions occur in a kinetically preferable metastable amorphous phase under conditions of fast precipitation of the substance from a solution, whereas a stable crystalline phase with no metal-metal contacts is formed by slow precipitation.  

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