A Semi-Empirical Potential for Simulations of Transition Metal Clusters: Minima and Isomers of Ni_n (n=2-13) and their Hydrides

Authors

E. Curotto, University of Rhode Island
A. Matro, University of Rhode Island
David L. Freeman, University of Rhode IslandFollow
J. D. Doll

Document Type

Article

Date of Original Version

1-8-1998

Department

Chemistry

Abstract

A potential energy surface (PES)for bare, mono and di-hydrogenated nickel clusters is constructed using the extended-Hϋckel approximation. The parameters are optimized and good agreement with theoretical and experimental results is obtained without including a posteriori coordination dependent terms. The global minimum and the first few low-lying isomers of several nickel clusters are investigated using a variety of minimization techniques. The difference in energy between isomers is much smaller than the Ni-Ni dissociation energy. Both geometric and optical isomers are found for many cluster sizes. In some cases symmetric nuclear configurations give rise to orbital degeneracies in the adiabatic surface which lead to distortions. The hydrogen atom is most frequently found on the surface. All isomers of Ni_nH2 contain a dissociated hydrogen molecule. The results are in good agreement with quantitative and qualitative experimental findings on this system.

Citation/Publisher Attribution

Curotto, E., Matro, A., Freeman, D. L., & Doll, J. D. (1998). A Semi-Empirical Potential for Stimulations of Transition Metal Clusters: Minima and Isomer of Ni_n(n=2-13) and Their Hydrides. Journal of Chemical Physics, 108(2), 729-742. doi: 10.1063/1.475433

Available at: http://dx.doi.org/10.1063/1.475433

Publisher Statement

© 1998 American Institute of Physics.