Recent works of Grabowski on molecules have shown the process of formation of hypervalent units due to different kinds of non-covalent interactions in secondary bonds, such as hydrogen, triel, tetrel, pnictogen, chalcogen, and halogen bonds, and have also pointed out that the mechanism of formation of these secondary bonds is the same . Moreover, it has been suggested that the hypervalent units formed by secondary bonds, leading to 3c-4e ERMBs in molecules follow the rules of the VSEPR model . Since the ERMBs have not been clearly distinguished in the diagrams of the hypervalent units in previous works , we have plotted in Fig. the simplest hypercoordinated units with ERMBs according to the VSEPR model . Curiously, some of the hypercoordinated units of Fig. , initially deduced for ERMBs, have been found to agree with those experimentally observed in amorphous and crystalline GST , and we have shown that the hypercoordinated units of crystalline GST as a PCM can be considered to have EDMBs. Moreover, we have shown that other hypercoordinated units, such as those formed by the Sb atoms in SbPO4 (Fig. ), those formed by Sb atoms in the square planar array of Sb atoms in BaZnSb2 (Fig. ), and those of the Ah and Ai phases of group-15 and -16 elements (Fig. ), also correspond to linear EDMBs. In view of these results, we tentatively conclude that the hypercoordinated multicenter units plotted in Fig. correspond to the simplest linear multicenter bonds that fulfill the VSEPR rules, irrespective of whether they are ERMBs (3c-4e) or EDMBs (3c-2e). In those hypercoordinated units, multicenter bonds can be directed along one, two, and three dimensions, alone or in combination with LEPs and ionocovalent bonds. Moreover, since our work shows that linear hypercoordinated multicenter units occur for both ERMBs and EDMBs in molecules and solids, we suggest, in agreement with previous works , that the "hypervalent" term should be replaced by "hypercoordinated", as shown in Fig. .