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T. Khmelevska, S. Khmelevskyi, P. Mohn:
"Magnetism and structural ordering on a bcc lattice for highly magnetostrictive Fe-Ga alloys: A coherent potential approximation study";
Journal of Applied Physics, 103 (2008), 0739111 - 0739115.

We calculate the electronic structure, magnetic moments, and ordering energies of highly
magnetostrictive Fe1-xGax alloys from first-principles in the composition range up to x=0.25. The
coherent potential approximation was used to treat effects of chemical disorder. Given an underlying
bcc lattice in whole range compositions investigated, the DO3 type of ordering is found to have a
lower energy than A2- and B2-type structures.We find that ordering energies strongly depend on the
state of magnetic order such that thermal magnetic disorder strongly favors chemical ordering DO3
and B2 . The values of the magnetic moments of Fe on different sublattices of ordered structures are
found to have a distinctive dependency on the Ga concentration. By taking into account the results
of earlier fully relativistic and full potential calculations of magnetostriction for ordered
stoichiometric Fe3Ga compounds and available experimental phenomenology, our results for
disordered alloys suggest an eventually more complex origin of the giant magnetostriction in Fe-Ga
alloys than it would appear from a simple electronic structure analysis of ordered stoichiometric
compounds. © 2008 American Institute of Physics.\