Proceedings of the 9th International Conference on X-Ray Absorption Fine Structure

J. Phys. IV France 7 (1997) C2-1197-C2-1198
DOI: 10.1051/jp4:19972191

Site Occupation Preferences in CdMnTeSe Quaternary Alloys. EXAFS Data Analysis

A. Kisiel¹, J. Lazewski^{1, 2}, M. Zimnal-Starnawska¹, E. Burattini³ and A. Mycielski<sup>4

1</sup>  Institute of Physics, Jagellonian University, ul. Reymonta 4, 30-059 Kraków, Poland
²  Institute of Nuclear Physics, ul. Radzikowskiego 152, 31-342 Kraków, Poland
³  Laboratori Nazionali di Frascati, INFN, via E. Fermi 40, 00 044 Frascati, Italy
⁴  Institute of Physics, Polish Academy of Science, Al. Lotników 32, 02-668 Warszawa, Poland

Abstract
Site occupation preferences in zinc-blende Cd_1-xMn_xTe_1-ySe_y (0≤x≤0.15; 0.0≤y≤0.20) quaternary alloys have been determined by the Extended X-ray Absorption Fine Structure (EXAFS) analysis. The experimental data have been collected with the use of synchrotron radiation for Se- and Mn-K edges. For both K edges, the preferences of manganese distribution around selenium have been observed and analyzed. The Mn-Se with Cd-Se, and Mn-Se with Mn-Te distances have been found as linearly dependent on concentration of Se and Mn. The average coordination numbers of Mn around Se versus Mn composition was approximated by the quadratic behavior instead of the linear dependence expected for the virtual crystal approximation, in which a full random distribution of elements in the sublattices is assumed. The obtained results support the preferential occurring of Mn and Se ions in the considered compounds. A structural and magnetic interaction reasons of the preferences were discussed.

© EDP Sciences 1997