Oscillatory relaxation of Al (110) reinvestigated by using medium-energy ion scattering

Medium-energy ion scattering (MEIS) has been used to investigate the room-temperature structure of clean Al(110). The motivation for this work was the presence of a significant discrepancy between two previous independent low-energy electron diffraction results concerning the sign of the third-to-fourth layer relaxation. We find a damped oscillatory contraction-expansion for the first three interlayer spacings. The relaxation results are (in percent change from the bulk interlayer spacing): Delta d(12) = -8.5+/-1 0%, Delta d(23) = +4.8+/-1.2% and Delta d(34)= -3.9+/-1.4%. These results are compared with other theoretical and experimental values. (C) 1998 Elsevier Science B.V. All rights reserved.