High coordination number lattice models

High Coordination Number Lattice Models of Real Proteins General Considerations... 

Interaction Scheme in High Coordination Number Lattice Protein Models... 

It is weU known that many materials, whether they have originally ionic, non-ionic, or molecular lattice stmctures, are transformed into the metallic state by the application of sufficiently high pressure, and indeed this can be expected to be tme of aU materials. Even quite modest increases in pressure can affect interatomic distances, spectral transitions, formal oxidation states, and many other phenomenological parameters, e.g. can increase the coordination number. Various attempts have been made in an effort to estabhsh relationships between pressure and these phenomenological parameters but none of them accounts satisfactorily for all of the observed features. This is almost certainly because of the absence, up to now, of a model which is capable of interpreting the facts without concerning itself with too detailed an interpretation of the binding forces. However, it will be shown here, after a brief survey of the present situation, that the functional approach seems to successfully provide such a model based as it is on an electron-pair donor-acceptor model of molecular interactions. 

It is worthwhile to mention that the DLL model can be considered as defining a special purpose parallel computer. A large number of microprocessors, each controlling the logic of a single lattice site, when arranged in an architecture of a spatial, highly coordinated lattice system could constitute a machine, the size of which and consequently the size of the simulated system will be limited less by the computation time than by the cost of... 

The existence of active sites on surfaces has long been postulated, but confidence in the geometric models of kink and step sites has only been attained in recent years by work on high index surfaces. However, even a lattice structure that is unreconstructed will show a number of random defects, such as vacancies and isolated adatoms, purely as a result of statistical considerations. What has been revealed by the modern techniques described in chapter 2 is the extraordinary mobility of surfaces, particularly at the liquid-solid interface. If the metal atoms can be stabilised by coordination, very remarkable atom mobilities across the terraces are found, with reconstruction on Au(100), for example, taking only minutes to complete at room temperature in chloride-containing electrolytes. It is now clear that the... 

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