The same reasoning would apply to consider the validity of the doublet rule for H, when it forms EDMBs at HP. In particular, polymeric H (…H-H-H…) at HP could be considered as a hypercoordinated A(0,0,1) unit (with no LEPs) with only one EDMB (1D geometry). Therefore, two electrons surround each H atom. In the end, assuming that each covalent bond, each LEP, and each EDMB, accounts for two electrons in multicenter hypercoordinated A(C, E, M) units, the doublet or octet rule is satisfied for the central atom A taking into account that 2(C+E+M) = 2 or 8. For the doublet rule, it has to be satisfied that C+M = 1 since in this case there is no LEP (E = 0). Therefore, H has only two possibilities, either it has only a covalent bond as in H2 or it has only an EDMB as in atomic/polymeric H at HP. For the octet rule, it has to be satisfied that C+E+M = 4. This is exactly the condition met by all the A(C,E,M) units in Fig. .