The 3-dimensional atomic coordinates of the (113)-3 x 1 surface were determined by analyzing in-plane and out-of-plane X-ray intensity data. As well as dimer and adatom motifs, which reduced the number of dangling bonds, a random distribution of sub-surface interstitials was identified. Such sub-surface interstitials relieved elastic stresses and lowered the energy of the electronic system. Together with the delicate balance between the energy gain due to the reduction of dangling bonds, and the energy costs due to induced strains, this determined the nature of the 3 x 1 reconstruction of (113).

H.Vogler, A.Iglesias, W.Moritz, H.Over: Physical Review B, 1998, 57[4], 2315-20