The concerted movements of weakly bonded Bi dimers on the Si(1 0 0)2×1 surface

It is found that Bi dimers in B positions (with axis perpendicular to Si dimer row) can make concerted movements in the same row. The estimated probability of such concerted movements of B dimers is at least by three orders of magnitude higher than unconcerted one. The evidence of weak interaction between dimers in the same row was found under detailed analysis of STM-images of neighboring Bi dimers. The interaction becomes visible in high-resolution STM-images as breaking of symmetry of neighboring Bi dimers with respect to symmetric free Bi dimer.