To discuss about the different nature of covalent, ERMBs, and EDMBs, we show in Regarding the linear I5 -anion, with a total of 36 electrons (average of 7.2 electrons per atom), one could think at first glance that it could be considered as forming an electronrich 5c-6e bond. This would lead to a scheme of molecular levels similar to those plotted for the 3c-4e bonds in Figure It is to be remarked that we have preferred the use of the term secondary bond in the previous paragraph as it possesses a broader group-wise meaning than the term halogen bond. It is to be noticed that neither a halogen bond view nor a secondary bonding picture are here fully adequate to describe the bonding in the linear I5 -anion. On the one hand, the halogen bond is linked to a nucleophile/electrophile interaction, according to IUPAC recommendation [53], forcing one to formally tear apart a well-defined molecule and picture it as arbitrary nucleophilic or electrophilic non-factual fragments (an always possible yet needless exercise). On the other hand, weak bonds in I5 -involve valence electrons, so they cannot be considered as mere "secondary Lewis acid-base interactions", as per original secondary bonding proposition From all the mentioned studies, it can be assumed that the electronic charge for the different iodine atoms in the infinite linear chain should be small and the same for all of them. Note also that for an infinite linear chain in a solid, such as that of Te -atoms in 4a