Thanks for taking the time to supply this information. It's much appreciated []

If i understand correctly, the formula would suggest that as a higher coordination number is responsible for an increased lattice energy this would result in an increased boiling/melting point. i think [?]

Yes, if you can assume the same variation of entropy between solid and liquid:

in the transition solid --> liquid the free energy changes of ΔG = ΔH - TΔS; where ΔH is the enthalpy of fusion, T is the (constant) temperature at which the process happen (= melting point) and ΔS = S

_{solid} - S

_{liquid}.

ΔH is > 0 so the process becomes spontaneous (= happens) only when T is high enough to make ΔG from positive to negative, that is ΔG = 0. But this means ΔH = TΔS and so T = ΔH/ΔS.

So, if you can assume the same ΔS, the more the coordination number, the higher U and so ΔH and so the higher the melting point T.