In order to avoid misinterpretation of Figs. and, it is important to stress, for the case of solids, that the hypercoordinated multicenter units in Fig. could be extended or replicated along the three spatial dimensions, e.g. the case of the rhombohedral and cubic units of the Ah and Ai phases of group-15 and -16 elements schematically represented in Fig. . The same extension to 3D must be also understood in relation to the sequence in Fig. . For instance, one primary covalent As-As bond in As-I is almost linearly linked (secondary bond) to two As atoms of neighbor layers (As•••As-As•••As) along one direction; thus, the trans influence of the two As•••As secondary bonds on the primary covalent As-As bond is on both sides of the As2 molecule. Moreover, since each As atom in As-I participates in three, almost perpendicular primary As-As bonds, this picture should be extended in the three, almost perpendicular directions. Consequently, extended 3D EDMBs are formed, leading to the Ah phase of As-II at HP, and not 3c-4e bonds, as previously assumed , and as Fig. -c could initially suggest due to its limited, schematic view.