Atomic stiffness parameter: A guide for patterning nanostructures
Résumé
The atomic stiffness parameter (ASP) in dense phases: S = 9νBε-1 where v stands for atomic volume, B for bulk modulus and ε for atomic cohesive energy expresses the competition between metallic attraction and core-core repulsion. ASP is driven by the repulsive interaction between electronic more or less filled internal shells since attractive metallic bonding is common for all metals. The square root of ASP was early introduced as anharmonicity parameter η by Rose et al. ASP controls the occurrence of local defects in crystalline structures. Since crystalline defects are essential for cluster structures, surface rearrangements and grain boundary structures, i.e. nanostructures, ASP also controls bulk malleability and ductility. The ASP set of composite materials controls their tendency to form quasicrystals and amorphous materials. Nanometric friction between materials also depends on respective ASP values. ASP values define several classes of metals, according to their ability to bear non-homogeneity. So called " extra stiff " metals have completely filled internal electronic shells, noble metals are " very stiff " while numerous metals are more or less smooth. This stiffness classification is linked with structural properties of nanostructures.
Origine : Accord explicite pour ce dépôt
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