The energy barrier to adatom formation was determined, by a simple analysis of the temperature dependence of the diffuse elastic peak obtained from inelastic He scattering measurements, to be 0.645eV for the (110) surface. Molecular statics calculations, performed using the embedded atom method, yielded a value of 0.680 to 0.770eV for detachment from {001}-faceted steps. Measurements at 2 different step densities indicated the same barrier height. Additional molecular dynamics simulations indicated that, at temperatures below 650K, no adatoms were created. At temperatures between 650 and 900K, adatoms were extracted from step edges and, at temperatures above 1000K, adatoms were generated by jumping out of the terraces.

Adatom Formation on the Ni (110) Surface W.Silvestri, A.P.Graham, J.P.Toennies: Physical Review Letters, 1998, 81[5], 1034-7