The easy mobility of strongly chemisorbed species on metal surface was in apparent contradiction with successive ruptures and formations of strong bonds implying high energy barriers. It was shown that adsorption energy was by far (2 orders of magnitude) larger than the energy allowing a shift of the surface metallic layer upon those beneath. Thus, an oxygen migration preserving strong oxygen–metal bonds by a slipping motion of the metal atoms beneath was energetically favorable. Strong surface restructuring occurred in heterogeneous catalysis whenever strongly bounded adsorbates were involved.

On the Move of Strongly Chemisorbed Species on Metals - the Example of O Diffusion on Pd(111) Surface. A.Markovits, C.Minot: Chemical Physics Letters, 2008, 458[1-3], 92-5