The Thermodynamics of Chromatography - Interactions Between the Atoms of Hydrogen, Carbon, Chlorine and Bromine and an Exclusively Dispersive Stationary Phase > Experimental Data > Page 41

Figure 15 Graph of Standard Enthapy against Atomic Polarizability

 

It would appear that the carbon in graphite would more likely simulate the carbon in an aromatic ring such as benzene than an aliphatic carbon similar to that in methane, The data for diamond was, therefore, chosen for correlation but the point for graphite is included in figure 15.

  

 

                                                          (26)

                         where (j) and (x) are constants.

Although there appears to be a linear relationship between polarizability and standard enthalpy of interaction, there is a constant of significant magnitude in the equation (x). This indicates that there is a contribution to the standard enthalpy that is independent of the atomic polarizability of the element concerned and may be some function of a physical property of the stationary phase.