1. Institute of Materials Science; TU Bergakademie Freiberg; Gustav-Zeuner-Str. 5 09596 Freiberg Germany
2. Institute of Nonferrous Metallurgy and Purest Materials; TU Bergakademie Freiberg; Leipziger Str. 34 09596 Freiberg Germany
3. Institute of Theoretical Physics; TU Bergakademie Freiberg; Leipziger Str. 23 09596 Freiberg Germany