Role of impurity elements in metal-metal bond strengths |
| |
Authors: | M A S Saq D G Pettifor |
| |
Institution: | 1. Department of Mathematics , Imperial College of Science and Technology , London, SW7 2BZ, England;2. Department of Crystallography , Birkbeck College, University of London , Malet Street, London WC1, England;3. Department of Mathematics , Imperial College of Science and Technology , London, SW7 2BZ, England |
| |
Abstract: | Abstract The influence of impurity elements on the strength of neighbouring metal–metal bonds is investigated using a simple tight-binding model. We show that the quantum-mechanical response function of the metal host plays a central role in determining whether the bond is weakened or strengthened. The Messmer–Briant model, which is based on classical concepts of charge flow due to differences in electronegativity, is not applicable to metals because of their perfect screening. Recent experiments on impurity core level and isomer shifts should not be taken as a direct measure of neighbouring metal–metal bond decohesion. |
| |
Keywords: | |
|
|