The structure of a metallic glass system using EXELFS and EXAFS as complementary probes

The short-range atomic order around all three constituent atoms in a prototypical bulk metallic glass (BMG) system was probed in a complementary way, using extended X-ray absorption fine structure for neighborhood of the higher atomic number elements, and extended energy loss fine structure (EXELFS) for the lower atomic number ones. The PdxNi(80 - x)P(20) system is a prototype for a whole class of BMG formers which are 80% transition metal and 20% metalloid. We find that the structure of these BMGs could be explained in terms of those of glasses at the end of the BMG range, namely, Pd60Ni20P20 and Pd30Ni50P20. The binary phosphide crystals near x = 0 and 80 are found to be simulate very well the local atomic structure of Pd30Ni50P20 and Pd60Ni20P20 glasses, respectively. The best glass former in this series, Pd40Ni40P20, is best described by a weighted average of Pd30Ni50P20 and Pd60Ni20P20 structures. (C) 2003 Elsevier Ltd. All rights reserved.