Skip to main content Accessibility help
×
Home

Atomic Scale Modelling of Supported and Assembled Nanoparticles

  • E. Zhurkin (a1), M. Hou (a2), H.Van Swygenhoven (a3), B. Pauwels (a4), M. Yandouzi (a4), D. Schryvers (a4), G.Van Tendeloo (a4), P. Lievens (a5), G. Verschoren (a5), J. Kuriplach (a6), S.Van Peteghem (a7), D. Segers (a7) and C. Dauwe (a7)...

Abstract

The properties of elemental and bimetallic free, supported and assembled nanoclusters are modeled at the atomic scale and the models are discussed on the basis of experimental observations. This way, the memory of some free cluster properties in nanostructured materials may be evaluated.

The combination of molecular statics with High Resolution Transmission Electron Microscopy (HRTEM) allows to predict fine detail of the lattice relaxation of a truncated octahedral gold cluster deposited on MgO. Metropolis Monte Carlo (MC) predicts that a lattice mismatch may contribute to disordering in deposited Cu3Au nanoclusters. In both Cu-Au and Ni-Al free clusters, offset of equilibrium stoichiometry may result in segregation of Au or Al at the cluster surface. An ordered stoichiometric core is surrounded by a disordered mantle where the excess species resides. Different modeling methods predict different nanometer scale textures.

Therefore, cluster assembled Ni3Al alloys formed by condensation and pressing are modeled in two different ways. Both make use of a combination of Molecular Dynamics and MC. Whatever the model nanostructure, the segregation properties of free clusters remain in the nanostructured material. This segregation is one possible cause that can inhibit the formation of a metastable martensitic phase as observed in bulk Ni-Al alloys.

The occurrence of vacancy clusters and voids is hardly identified by HRTEM. On the other hand, their distribution and sizes are sensitive to the nanostructure modeling. Therefore, a new characterization method is developed, which combines positron lifetime spectroscopy with the calculation of positron lifetimes from selected areas of the model samples.

Copyright

References

Hide All
1. Pauwels, B., Tendeloo, G. Van, Bouwen, W., Kuhn, L. Theil, Lievens, P., Lei, H. and Hou, M.; Phys. Rev. B62, 15 (2000) 10383. B. Pauwels, G. Van Tendeloo, E.E. Zhurkin, M. Hou, G. Verschoren, L. Theil Kuhn, W. Bouwen and P. Lievens; submitted for publication.
2. Hou, Q., Hou, M., Bardotti, L., Prével, B., Mélinon, P. and Perez, A.; Phys. Rev. B62, 4 (2000) 2825; L. Bardotti, B. Prével, P. Mélinon, A. Pérez, Q. Hou and M. Hou; Phys. Rev. B62, 4 (2000) 2835
3. Gleiter, H., Prog. Mater. Sci, 33 (1989) 223
4. see e.g. Edelstein, A.S., Cammarata, R.C. in “Nanomaterials: Synthesis, properties and Applications” (Inst. of Physics Publ., Bristol and Philadelphia, 1996)
5. see e.g. Frenkel, D. and Smit, B.; “Understanding Molecular Simulation” (Academic Press, San Diego, 1996)
6. Parinello, M. and Rahman, A.; J. Appl. Phys., 52 (1981) 7182
7. Zhurkin, E.E. and Hou, M.; J. of Physics C12 (2000) 6735
8. Acjland, G.J. and Vitek, V.; Phys. Rev. B41 (1990) 10324; F. Gao, D. Bacon and G.J. Ackland; Phil. Mag. A67 (1993) 275
9. Hou, Q., Cayphas, J-M. and Hou, M.; in “Advances in mechanical behaviour, plasticity and damage”, ed. By Miannay, D., Costa, P., François, D. and Pineau, A. (Elsevier, Amsterdam, 2000) 287.
10. Kuriplach, J. et al. this conference; S. Van Peteghem et. al.; this conference

Atomic Scale Modelling of Supported and Assembled Nanoparticles

  • E. Zhurkin (a1), M. Hou (a2), H.Van Swygenhoven (a3), B. Pauwels (a4), M. Yandouzi (a4), D. Schryvers (a4), G.Van Tendeloo (a4), P. Lievens (a5), G. Verschoren (a5), J. Kuriplach (a6), S.Van Peteghem (a7), D. Segers (a7) and C. Dauwe (a7)...

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed