REDISTRIBUTION OF LA-AL NEAREST-NEIGHBOR DISTANCES IN THE METALLIC-GLASS AL0.91LA0.09

X-ray-absorption fine-structure (XAFS) measurements of metallic glass Al0.91La0.09 and a crystalline phase Al11La3 formed by annealing of th e glass were made at the La L(3) edge and analyzed by the splice metho d. The first-neighbor partial radial distribution functions about the La atoms for the crystal and glass were obtained at T=12 K demonstrati ng the difference between their local structures. The shortest La-Al d istance (mean value 3.09+/-0.05 Angstrom) within the glass was distinc tively smaller than within the crystal Al11La3 (3.21+/-0.05 Angstrom). This partial shortening of the La-Al bonds decreases the size mismatc h between the La and Al atoms making the glass formation more favorabl e with anomalously low content of La during the quench. Monte Carlo si mulations were performed for the Al-La glass and agreement with the XA FS result was obtained.