A CRITICAL DISCUSSION ABOUT THE ROUGHENING TEMPERATURE ESTIMATION - THE AG(110) CASE

The thermal behaviour of Ag(110) is investigated with energy-resolved He-atom scattering in the temperature range 420-980 K and the informat ion gathered from the evolution of the diffracted peak shape with temp erature is discussed. First of all a possible crossover of the short-r ange surface behaviour to the asymptotic one for distances comparable to the instrumental transfer width is excluded. Moreover an estimation of the roughening temperature is given, taking into account distortio ns in the scattered line shape induced from inelastic contributions to the diffracted intensity, from finite surface correlation length and from different sample cleaning treatments.