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editing(melting): Describing melting point
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This describes why a better fit for the melting point is not chosen.

Fixes #24
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malramsay64 committed Dec 17, 2019
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Expand Up @@ -622,31 +622,20 @@ These values are obtained from the fitting in
@fig:normalised_melting {#tbl:rate_coefficient}

The lines depicting the fit of
the Wilson-Frenkel theory in @fig:normalised_melting
the Wilson-Frenkel theory in @fig:normalised_melting_all
predict significantly slower melting rates
than observed in the simulations
for temperatures $T/T_m > 1.20$.
A possible cause for this would be the onset of spinodal
with the melting occurring throughout the structure,
which is definitely not observed.

It should be noted that the high spinodal temperature
doesn't support a super stable crystal state,
the crystal only has a small potential energy benefit over the liquid state
and the melting rate of the crystal
increases well above that predicted
by the Wilson-Frenkel model.
Instead it is indicative of the rarity of nucleation events,
being the formation of defects within the crystal.
There are defects which form within the crystal,
shown in @fig:melting_disorderB,
however these are transient defects,
stable within the crystal structure
and unable propagate melting.
The defects in @fig:melting_disorderB
are similar to the defect
which propagates the solid state phase transition
of the p2gg crystal to the p2 crystal (@fig:solid_state_transition_structure).
through this is not observed.
When only looking at the temperatures close to the melting point
[@fig:normalised_melting_zoom]
the data would seem to fit a melting point at 0.97,
slightly lower than was predicted by observing melting.
Without observing crystal growth,
the melting point is going to be an estimated value,
and the current estimate is within the error of the simulations.

:::{class=subfigure id=normalised_melting_fit}

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