Figure 1

Temperature-dependent EXAFS data for the Fe isotope substituted samples.
(a) Representative experimental EXAFS oscillations at the As (upper panel) and Fe (lower panel) K-edges of the 54Fe-sample. (b) FTs of the As K-edge EXAFS data measured cooling the sample down to 10 K. (c) Comparison between the first-shell peak of the FTs of the 54Fe- and 56Fe-samples at 10 K. (d) The same of (c) at RT.