Neglected adsorbate interactions behind diffusion prefactor anomalies on metals - art. no. 125423

Highly anomalous values for the preexponential factor in atomic diffusion r ates at surfaces have recently been inferred from scanning-tunneling micros copy growth experiments. In an extensive first-principles kinetic Monte Car lo study, we show how long-range adsorbate interactions invalidate the stan dard nucleation-theory approach to analyzing experimental island-density da ta. When adatom-adatom interactions are properly accounted for in the analy sis of experimental data, the anomaly is lifted, and deduced prefactors are consistent with direct theoretical calculations. We show that the dependen ce of the island density on the growth rate is modified by interactions. wh ich could be used to identify adsorbate interactions in growth experiments.