Isomerization and Melting of Small Alkali-Halide Clusters
The nature of phase transformations in small alklai-halide clusters is investigated using molecular dynamics simulations. On the basis of systematic studies of clusters of variable sizes, it is concluded that the kinetics and dynamics of the transformations depend on system size. For small clusters, distinct, diffusionless, isomerization occurs. Intermediate size clusters exhibit hierarchical kinetics with isomerizations preceding the onset of diffusion and eventual melting. True sharp melting transition and solid-liquid coexistence is found only for relatively large clusters. This sequence of physical processes versus size can be modeled as a gradual opening of the accessible phase-space and the coalescence of time scales distinguishing intra-well and inter-well dynamics.
KeywordsSmall Cluster Soft Mode Coexistence Region Eventual Melting Neighbor Coordination
Unable to display preview. Download preview PDF.
- 4.R. W. Hockney and J. W. Eastwood, Computer Simulation Using Particles, (McGraw-Hill, N.Y., 1981), pp. 488–498.Google Scholar
- 7.For recent reviews see: F. F. Abraham, J. Vac. Sci. Technol. B2, 534 (1984);Google Scholar
- 7a.U. Landman et al. in Mat. Res. Soc. Proc. 63, 273 (1985).Google Scholar
- 8.This is reminiscent of the picture advanced by F. M. Stillinyer and T. A. Weber for a liquid, see: Kinam A5, 159 (1981);Google Scholar
- 10.D. A. McQuarrie, Statistical Mechanics, (Harper and Row, N. Y., 1976), Chap. 21, 22.Google Scholar