Surface Diffusion of Co on Ni(111) Studied by Diffraction of Optical Second-harmonic Generation off a Monolayer Grating

Diffraction of optical second-harmonic generation from a monolayer grating created by laser desorption of adsorbates can be used to study surface diffusion of molecules on substrates. Application of this novel technique to CO on Ni(111) yields a diffusion activation energy of 6.9 kcal/mol and a preexponential factor of {}1.2 ×{} 10^-5 cm² s^-1.