As is stated above the bulk melting transition is preempted by the surface melting transition and therefore can not be observed experimentally (at standard conditions). The aim of this part of our research was to investigate the phenomenon of surface disordering and premelting.
The questions that are addressed in our computer simulations are following:
What is the thermodynamic melting point at which the solid starts to melt from the surface in our model?
How the structural, transport and energetic properties of the solid change
at the surface region as a function of temperature?
At which temperature surface disordering and premelting begins and an adlayer appears on the top
of the surface layers ? Whether surface premelting of
various low-index bcc faces of vanadium is different (anisotropy)?
If the phenomenon is anisotropic, whether the anisotropy ``follows''
the packing structure of the vanadium faces ( e.g. one could expect
the least packed surface (111) begins disorder first, while the close packed surface (011)
may preserve its crystalline structure up to
)?
Of course, this is not a complete list of questions which might be asked,
the list can be easily continued furthermore. However, the main question,
to which we want provide the answer, was whether the Born scenario for the
bulk melting transition (e.g. the concept of a critical volume) can be applied
to explain the surface melting?
In the following section we will try to answer these questions.