J. Kuriplach1,2, M. Sob3, C. Dauwe1
1 Department of Subatomic and Radiation Physics, University of Gent, Proeftuinstraat 86, B-9000 Gent, Belgium,
2 Department of Low Temperature Physics, Charles University, V Holesovickach 2, CZ-180 00 Prague 8, Czech Republic,
3 Institute of Physics of Materials, Academy of Sciences of the Czech Republic, Zizkova 22, CZ-616 62 Brno, Czech Republic
The effect of preferential positron annihilation in binary Fe-Al system is studied by means of the LMTO electron and positron structure method. The study covers the whole concentration range from Fe to Al. The supercell approach is utilized to model the structure of alloys. We conclude that positron preferential occupation of Fe sites is negligible for small Al concentrations and increases with Al content. The effect of positron preferential annihilation at Fe sites is also negligible, if there is any. The nonlinear dependence of positron annihilation rate on Al concentration can be almost fully explained as a volume effect.