Field-Ion Microscope Observations of Indirect Interaction between Adatoms on Metal Surfaces

From field-ion microscope kinetic and equilibrium experiments with rhenium adatoms on W(110) planes it is found that the interaction potential energy between two adatoms exhibits an oscillatory behavior. The cohesive energy between two adatoms is very small, only {~}0.16 eV at the closest separation. These observations are in general agreement with the indirect adatom interaction models as proposed and discussed by various investigators.