Energetic Aspects of Ionic Bonding

It is important to stress that the formation of an ionic bond involves two opposing energetic aspects. Creation of the two ions independently of each other requires an investment of energy that is, this raises the energy of the system relative to that of the atoms. 

For example, consider the generation of Na and Cl from their respective atoms. We can generate the ions in two steps  

using as an example Na+ and Cr, this lowering of the energy proportional to the Qci product (which is -1) divided by the distance / Naci- Thus, the sign of the energy due to the attraction is negative, which means that the attraction lowers 

The Origins of the Law of Nirvana in Ionic Bonds So why do we have Na Cl and not, for example, Na Cl , which will certainly render four times as much lowering of the energy This is because the creation of Na requires ejection of the second electron from the exposed valence shell, which has achieved an octet as Na, and simultaneously creating Cl , which exceeds the octet. This would be a huge investment, which would not be overcome by the Coulomb attraction between the 

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