We have observed homogeneous crystal nucleation in Lennard-Jones liquid by molecular dynamics simulations. A clear nucleation time delay has been observed at T=0.677 Tm and T=0.629 Tm indicating the presence of a barrier, in contrast to recent reports. The structure of nuclei observed in the previous results and in the present work is evidence of transient-time dominated nucleation, not of a spinodal. Very rapid nucleation is observed at T=0.484 Tm, indicating either a low (but finite) barrier or possibly a spinodal transformation. No spinodal effect has been observed in similar simulations of crystal nucleation in aluminum at any temperature, suggesting that different qualitative behaviors may be possible in what would seem to be similar potentials.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 8 Jul 2008|