Short range structure of amorphous Se100-xAsx prepared by mechanical alloying

Amorphous Se100-xAsx samples were synthesized by mechanical alloying. Short range structure for these samples during amorphization process was observed by neutron diffraction. When the amorphization proceeds, the coordination number of the nearest Se atoms around a Se atom decreased with increasing milling time and approached 1.91 +/- 0.02 atoms for pure Se. Moreover, the coordination number of As-As and Se-Se pairs decreased and that of the As-Se pair increased to be 2.63 +/- 0.03 atoms after 150 hours of milling of the Se(60)A(40) sample. These results definitely indicate that a number of dangling bonds exist in the amorphous Se100-xAsx prepared by mechanical alloying, in comparison with those prepared by liquid quenching. (C) 1999 Elsevier Science B.V. All rights reserved.