If growth is continuous (all adsorption sites equivalent), then a simple model can be
used to relate growth velocity to undercooling. (During lateral growth, the velocity is
expected to be slower, for a given undercooling, because there are fewer adsorption
sites.)

An adsorption event is assumed to be similar to a normal diffusive jump in the liquid.

This is simulated schematically. When "Adsorb Molecule" is clicked.
The advance velocity from adsorption events can be written as the product of jump
distance, l*, vibration
frequency, w_{0},
and the probability of making a diffusive jump Account must also be taken of
desorption events. These are less frequent (if the interface is undercooled) because of
the larger energy barrier