Since the PBEsol functional works well below 6 GPa, we have simulated the monoclinic phase of Bi-II to be sure about the occurrence of MMBs in the HP phases of Bi. The monoclinic Bi-II phase has a distorted sc structure with a very narrow stability pressure range between 2.5 and 2.7 GPa that undergoes a transition to the incommensurately modulated host-guest Bi-III structure above 2.7 GPa (Bi-III is isostructural to Sb-II, the HP phase of Sb above 9 GPa ). Our results for the optical phonons of Bi-II at HP (see Fig. in ESI) show a rather good agreement with experimental results and a positive pressure coefficient for all optical modes, as expected once MMBs are formed. On the other hand, the calculated value of Z* in Bi-II shows much larger values than expected for a material with covalent or metallic bonds. Therefore, we conclude that the slightly distorted sc phase of Bi-II likely shows asymmetric MMBs, similar to the symmetric MMBs of As-II.