Additional support for the equivalence between MMBs and EDMBs comes from symmetry and energy arguments. According to Lubchenko and coworkers , the ERMB has been only observed in linear molecules with 3c-4e bonds since this is the only energetically stable configuration. The reason is that a system with n centers and (n+1) electrons is only stable if the n+1 electrons fill (n-1) localized molecular orbitals. This means that n+1 = 2(n-1), whose only solution is n = 3 . This result agrees with simulations that showed the weak and easily perturbed bonds in the linear I5 ꟷ molecule . The above reasoning explains that ERMBs are mainly found in linear 3c-4e bonds in one, two, and three dimensions, e.g. in I3 ꟷ , XeF2, XeF4, and XeF6 molecules. These 3c-4e bonds can also be encountred in molecules inside solids, such as I3 ꟷ in CsI3 and TeI6 2ꟷ in Cs2TeI6. In these two last compounds, Cs atoms give their electrons to the I3 and TeI6 molecular units to form I3 ꟷ and TeI6 2ꟷ molecular units that are linked to Cs atoms by ionic bonds. Our calculations confirm that ERMBs are located inside the molecular I3 ꟷ and TeI6 2ꟷ units. In CsI3, Cs 0.27+ atoms give charge to the three I atoms of the I3 ꟷ molecule that show different negative charges similar to those of Fig. . Note that in the I3 ꟷ units of CsI3 at RP, there are two slightly different I-I bonds (one short and one large) that tend to form two equal ERMBs at HP as shown by the linear array in Fig. . On the other hand, the atomic charge in Cs2TeI6 is distributed as: Cs 0.76+ , Te 0.80+ , and I 0.39ꟷ . This means that the TeI6 2ꟷ units (see Fig. ), which form a cubic array as in Fig. , have a Te atom that also gives almost one electron to the I atoms. Therefore, as expected for linear 3c-4e ERMBs (in this case in three perpendicular directions), the external I atoms concentrate the electronic charge, so this cubic TeI6 2ꟷ unit behaves as a pseudo-SbI6 3ꟷ unit that is isoelectronic to XeF6; a molecule that also exhibits one of the two geometries in 3c .