Redistribution of La-Al nearest-neighbor distances in the metallic glas

X-ray-absorption fine-structure (XAFS) measurements of metallic glass (Formula presented)(Formula presented) and a crystalline phase (Formula presented)(Formula presented) formed by annealing of the glass were made at the La (Formula presented) edge and analyzed by the splice method. The first-neighbor partial radial distribution functions about the La atoms for the crystal and glass were obtained at T=12 K demonstrating the difference between their local structures. The shortest La-Al distance (mean value 3.09±0.05 Å) within the glass was distinctively smaller than within the crystal (Formula presented)(Formula presented) (3.21±0.05 Å). This partial shortening of the La-Al bonds decreases the size mismatch between the La and Al atoms making the glass formation more favorable with anomalously low content of La during the quench. Monte Carlo simulations were performed for the Al-La glass and agreement with the XAFS result was obtained.