Influence of the Magnetic Moment on the Atomic Distance in Amorphous Ce_xRu_100-x

We perform the extended x-ray absorption fine structure (EXAFS) measurement to investigate the local structure of amorphous alloys Ce_xRu_100-x (x=9, 43 and 80). The interatomic distances of the nearest Ru–Ce and Ru–Ru pairs derived from EXAFS are fully independent of Ce concentration. On the other hand the distance between neighboring Ce atoms increases sharply with the Ce content, which is exactly proportional to the Ce effective magnetic moment. We discuss the relation between the atomic distance and the effective magnetic moment from the point of view of the magneto-volume effect.