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Dimer Configuration Gallery

Silicon Ad-Dimer Orientations and Energies






A-Dimer.







B-Dimer Theory: +0.08eV
Expt: +59 + 9 meV


C-Dimer Theory: +0.18eV
Expt: +61 + 16 meV



D-Dimer Theory: +0.76eV
Dimer config's A-D
Fig. 2 Silicon Ad-Dimer Orientations and Energies on Si (001). The black dots in this figure represent the silicon atoms making up the (001) reconstructed surface. The configurations are arranged in descending order according to the energies calculated by Yamasaki et al. Energies (per dimer) are given here relative to that of the type A dimer. At room temperature a limited number of B-type and frozen in C-type dimers can be observed, while the less stable D-type require elevated temperatures.



A or B-Dimer
Fig.2a/b. On Top of the Rows Dimer. In our temperature range, an ad-dimer switches rapidly between the two on top of the row configurations, A and B as can be seen. At elevated temperatures the dimer diffuses so quickly that it images as a streak along a row.
C-Dimer
Fig.2c. C-Dimer. In comparison to the A and B-dimers, the C is a faint, between the rows feature. See the C-Dimer page of the Gallery for an animation of a dimer's diffusion across rows, through the metastable C-state.




G. Brocks and P. J. Kelly. Dynamics and Nucleation of Si Ad-dimers on the Si(100) Surface, Phys. Rev. Lett. 76, 2362-2365 (1996.)

T. Yamasaki and T. Uda. Initial Process of Si Homoepitaxial Growth on Si(001), Phys. Rev. Lett. 76, 2949-2952 (1996.)