  The classical nucleation theory for homogeneous nucleation is formulated as a
theory for a density fluctuation in a supersaturated gas at a given
temperature. But Molecular Dynamics simulations reveal that it is small cold
clusters which initiates the nucleation. The temperature in the nucleating
clusters fluctuate, but the mean temperature remains below the temperature in
the supersaturated gas until they reach the critical nucleation size. The
critical nuclei have, however, a temperature equal to the supersaturated gas.
The kinetics of homogeneous nucleation is not only caused by a grow or shrink
by accretion or evaporation of monomers only, but by an exponentially declining
change in cluster size per time step equal to the cluster distribution in the
supersaturated gas.
