Once confirmed the metavalent character of MMBs in the octahedrally-coordinated phases of pnictogens and chalcogens, to finish this section, we want to remark that the multicenter character of the unconventional bond in the Ah and Ai phases of group-15 and -16 elements is consistent with previous calculations in PCMs characterized by the IpCOHP(2c) and the ICOBI(3c) values . For that purpose, we have analyzed the values of the IpCOHP(2c) along the primary and secondary bonds of the A7 and A8 structures in pnictogens and chalcogens, respectively, at different pressures and also the ICOBI(3c) along the two bonds.