Alloy theory

In the early days of alloy theory, Lifshitz argued on intuitive grounds that one can calculate the properties of a disordered alloy from one sufficiently large sample," and referred to this property of a large sample as self-averaging. It can be seen most easily in exact... 

Experimentally it is found that the Fe-Co and Fe-Ni alloys undergo a structural transformation from the bee structure to the hep or fee structures, respectively, with increasing number of valence electrons, while the Fe-Cu alloy is unstable at most concentrations. In addition to this some of the alloy phases show a partial ordering of the constituting atoms. One may wonder if this structural behaviour can be simply understood from a filling of essentially common bands or if the alloying implies a modification of the electronic structure and as a consequence also the structural stability. In this paper we try to answer this question and reproduce the observed structural behaviour by means of accurate alloy theory and total energy calcul ions. 

Application of the Coherent Potential Approximation (CPA) alloy theory in connec-... 

SPR-KKR can. straightforwardly be combined with the CPA alloy theory to deal with disordered alloys. 

Anderson AB, Roques J, Mukeijee S, Murthi VS, Markovic NM, Stamenkovic V. 2005. Activation energies for oxygen reduction on platinum alloys Theory and experiment. J Phys Chem B 109 1198-1203. 

Rajput, S.S., Prasad, R., Singru, R.M., Triftshauser, W., Eckert, A., Kogel, G., Kaprzyk, S. and Bansil, A. (1993) A study of the Fermi surface of lithium and disordered lithium-magnesium alloy theory and experiment, J. Phys. Condens. Matter, 5,6419-6432. 

Pettifor, D.G. (2000) Controversial concepts in alloy theory revisited. In The Science of Alloys for the 21st Century, eds. Turchi, E.A., Shull, R.D., Gonis, A. (TMA, The Minerals, Metals and Materials Society, Warrendale, Pennsylvania), p. 121. 

Sanchez, F. J (1984) in High Temperature Alloys Theory and Design, ed. Stiegler, 0. (Met. 

In alloy theory, this equation determines the variational wave function for an atomic cell I/, embedded in a statistical medium defined by the vector of coefficients ft for all other cells [157, 281]. 

Nesbet, R.K. (1992). Full-potential revision of coherent-potential-approximation alloy theory, Phys. Rev. B 45, 13234-13238. 

Until recently, one might have considered this immense collection of experimental information as one of the major experimentally gathered, but theoretically unexplained, bodies of data in all of the chemical sciences. As shown above, however, in recent years major progress has been made on the theory of alloys and in estabhshing empirical or semiempirical correlations for alloy phase formation this, in turn, has benefited phase diagram prediction, which remains an important goal of computational alloy theory. Two principal approaches exist, which are presently in the process of slow convergence. 

At present, inclusion of the hquid into such calculations requires use of fitted free energy curves, such as those used in the more empirical approach described below, but as liquid alloy theory advances, this situation will improve. Thus, complete phase diagram calculations based on pseudopotential calcnlations have been presented by Hafher. ... 

Acu] Acuna, J., Sanchez, M., Luraschi, A., Metal-Slag And Slag-Gas Equilibria in the Cu-Fe-0 System in Alloy Theory And Phase Equilibria , Proe. Conf, Buenos Aires 1985, ASM, Metals Park, Ohio 44073 USA, 91-95 (1986) (Experimental, Phase Diagram, 12)... 

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