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B N J Persson

Publications and source records attributed to B N J Persson.

3 recordsLinked to original sources

Adhesion between elastic bodies with randomly rough surfaces.

I have developed a theory of adhesion between an elastic solid and a hard randomly rough substrate. The theory takes into account the fact that partial contact may occur between the solids on all length scales. I present numerical results for the case where the substrate surface is self-affine fractal. When the fractal dimension is close to 2, complete contact typically occurs in the macroasperity contact areas. For a fractal dimension larger than 2.5, the area of (apparent) contact decreases continuously when the magnification is increased.

Journal Article↗

Lateral hopping of molecules induced by excitation of internal vibration mode.

We demonstrate electron-stimulated migration for carbon monoxide (CO) molecules adsorbed on the Pd(110) surface, which is initiated by the excitation of a high-frequency (HF) vibrational mode (C-O stretching mode) with inelastic tunneling electrons from the tip of scanning tunneling microscopy. The hopping phenomenon, however, cannot be detected for CO/Cu(110), even though the hopping barrier is lower than in the CO/Pd(110) case. A theoretical model, which is based on the anharmonic coupling between low-frequency modes (the hindered-translational mode related to the lateral hopping) and the HF mode combined with electron-hole pair excitation, can explain why the hopping of CO is observed on Pd(110) but not on Cu(110).

Journal Article↗