In
addition,
| where (r) | is the density of the medium, |
| (M) | is the molecular or atomic weight, |
| (NA) | is Avogadro's Number |
| and (PM) | is the molar (or atomic) polarizability, noting that the number of molecules per unit volume is Nr/M. |
.
If the dispersive interactive energy, is directly related to the standard enthalpy of interaction, then,
Consequently, DHo a Pm
The standard enthalpy for hydrogen, carbon, chlorine and bromine are plotted against their atomic polarizability and the resulting linear curve is shown in figure 15 (index of determination 0.996). There is a choice for the pertinent data for carbon. The dielectric constants of graphite and diamond are similar, but their densities are significantly different,
