The electric field gradient for single indium atoms on low-index silver surfaces

Abstract
The perturbed gamma gamma angular correlation (PAC) method has been applied to study isolated 111In atoms on low index silver surfaces. Strong, axial-symmetric electric field gradients are observed on the highly symmetric (111) and (100) surfaces, whereas a non-axial-symmetric field gradient is found for the (110) orientation. Strength and symmetry of the electric field gradients have been studied as a function of measurement temperature. The influence of impurities on the field gradient distributions is discussed. Finally, a comprehensive comparison is given to results reported previously for 111In on the respective copper surfaces. The observed behaviour reflects well known features of the bulk metals.