J. Phys. IV France 7 (1997) C2-1005-C2-1006
Local Structural Distortions in Quenched Au-Cu AlloysA.I. Frenkel1, E.A. Stern1, A. Rubshtein2, A. Voronel2 and Yu. Rosenberg2
1 Physics Department Box 351560, University of Washington, Seattle, WA 98195-1560, U.S.A.
2 Sackler School of Physics and Astronomy, Tel-Aviv University, 69978 Tel-Aviv, Israel
Disordered alloys AuxCu1-x prepared by melt spinning method were analyzed by XAFS taken at 80 K. Local atomic structure around Au and Cu atoms was measured and strong deviations from perfect fcc structure were obtained resulting from the size disparity between Au and Cu atoms. A sharp asymmetry was found between the shorter (Cu-Cu) and the longer (Au-Au) nearest neighbor bond lengths. Average first nearest neighbor distance was found greater than obtained using linear interpolation of the pure components. Results on Debye-Waller factors showed strong concentration dependence for the Cu-Cu bond, suggesting the loosening of contact between these atoms when the concentration of Au increases.
© EDP Sciences 1997