In Figure the scalar and fully-relativistic band structure is shown in a narrow energy range around EF. In the case of RbBi2, when SOC not included, the Fermi level is positioned in the flat part of DOS, while with SOC the local maximum appears and Fermi level is situated on its slope. The parabolic bands around Γ point with a large (3 eV) energy gap around the Fermi level are not affected by SOC. At many points of k-space (for example between K and U or X and Γ points), mainly below tge Fermi level, the band crossings are removed by SOC.