EXFAS STUDIES ON THE THERMAL-BEHAVIOR OF COPPER SURFACE

The crystalline structure of copper surface has been studied by means of the Extended Fine Auger Structure spectroscopy as a function of the sample temperature. The oscillating features observed beyond the Cu M 2,3VV Auger transition, due to an autoionization process involving the 3p and d-valence band electrons, have been analysed following the Ext ended X-ray Absorption Fine Structure theory, when the sample temperat ure grows from 300 K to 900 K. As the temperature increases no shift o f the nearest neighbour distances but a sizeable increase of the Debye -Waller factor have been observed. The results show the capability of the EXFAS technique to follow the thermal behaviour of the surface str ucture of solids with higher surface sensitivity than other electronic spectroscopies.