and "In the solid phase (and in the liquid phase to the best of my knowledge), sodium and chloride ions are not paired up and do not form discernible molecules of NaxClx. In in the gas phase they do, as this is lower-energy than separate gas-phase ions. My knowledge of the literature of this is not large, but I have heard that gas phase sodium chloride consists of molecules of Na2Cl2.
Likewise, sodium chloride in the gas phase consists of molecules, and (I’m told) they have a particular structure and composition. A molecule of Na1Cl1 will be quite different than a molecule of Na2Cl2. In th…