the ordered faceted phase.

![Snapshot of the surface at T=1.17 on cooling. []{data-label="figure4"}](fig4){width="8cm"}

It is very interesting that in the disordered phase the surface is not planar as suggested in experimental works [@song95]. The structure of disordered phase contains randomly distributed small facets mainly of $\{112\}$ orientations what is shown in Fig. \[figure5\] where the cross section of the disordered phase is compared to cross sections of faceted {211} and ideal bcc(111) surfaces. Moreover, we calculated the average number of atoms on a facet of orientation (211) which in the disordered phase is nearly 10. So we will call this phase as disordered faceted phase (DFP). In very narrow temperature range, we observed a coexistence of a faceted $\{112\}$ and DFP, e.g., in simulation at $T=1.23$ denoted by the triangle in Fig.  \[figure2\]. A surface structure in this case looks like surface of ordered phase where large pyramids are removed and on their place DFP is present. On the other hand, there are 3-sided pyramidal holes built of large facets of $\{112\}$ orientation. Sometimes, DFP is located also at the bottom of these holes. It is worth noting that coexistence of both faceted and disordered phases has been observed [@song95] 