ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
We have developed an ab initio method for calculating the static correlation functions in substitutional alloys, which, for example, describes their atomic short-range order (ASRO) as given by atomic diffuse scattering intensities. For magnetic alloys, a contribution to the total diffuse scattering intensities also results from the moment-chemical correlations (i.e., variations of local moments due to changes in the chemical environment). The response functions, which may be directly compared to single crystal neutron-scattering, are derived from a mean-field statistical mechanical description of compositional fluctuations in alloys. The statistical averages are performed via the Korringa–Kohn–Rostoker coherent-potential approximation, which incorporates the electronic structure of the high-temperature, chemically disordered state. For magnetic Fe-13.5% V alloys, we present results of first-principles calculations of the ASRO, which compare very well with the (quenched) single crystal data obtained by Cable et al.,1 and predict the structure of the moment-chemical correlations. Moreover, we determine the origin of the q-dependent structure in these correlations. In the future, this will allow direct comparison of neutron data with theory to understand more fully the underlying mechanisms which drive, e.g., ASRO.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.348788
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