Atomic Short Range Order and Pair Interaction of Disordered Au₄Mn by Neutron Diffraction

Abstract

Atomic diffuse scattering from a single crystal of Au 4 Mn with the disordered fcc structure was observed by neutron diffraction in the three dimensional reciprocal space. A cigar type diffuse pattern along the line of [1, K , 0] with three broad maxima at K =0.27, 0.50 and 0.73 was obtained. After some corrections and an arrangement of the pattern at the equivalent positions in the reciprocal space, the parameters of atomic short range order and pair interaction up to the 50th neighbor were determined by a method presented by Adachi-Nakashima: J. Phys. Soc. Japan 40 (1976) 25. The reproducibilities from the order parameters and the pair interactions thus determined were examined. The former gives a good reproducibility but the latter not. Origins of the pair interaction of this alloy were discussed.