Metals change their mettle

European scientists used synchrotron X-ray microbeams to observe how the microscopic structure of a crystalline material fluctuates in time even when the temperature remains constant. The study shows in microscopic detail how a metal alloy, composed of iron and aluminum, changes when heated. In contrast to conventional wisdom, the researchers discovered that one class of interference peaks associated with the low-temperature structure disappears, while another class of peaks belonging to the new structure emerge at the same temperature. This gives clearcut evidence that temporal structural fluctuations on an atomic scale are present in the crystal and could lead to new insights in the field of condensed matter science.