University of Iceland, Science Institute (UI)

Principal investigator: 
Hannes Jónsson

Research

The main focus of research in the Jónsson group is the prediction of mechanism and rate of transitions on the basis of first principles evaluation of the energy and atomic forces. The group has expertise in the use of rate theory, both harmonic [57, 74, 75] and full, anharmonic transition state theory [76, 77], classical as well as quantum mechanical [78]. By incorporating these methods into a kinetic Monte Carlo procedure, the long time scale evolution of solids has been simulated [79]. The group has, in particular, studied the formation and migration of self-trapped excitons in oxides [80, 81]. In order to describe well enough electronic defect states, such as trapped holes, excess electrons and excitons, the group has developed a self-consistent implementation of revised self-interaction corrected density functional theory which can be applied to condensed phase systems subject to periodic boundary conditions.

Facilities and infrastructure

The group is the major user of a 130 node Beowulf cluster (2.8 GHz Pentium 4 CPUs with 1GB of memory each) located at the University of Iceland. The group also has a large allocation of CPU time on the 980 node MPP2 parallel computer at PNNL in Richland WA, USA (1.5 GHz Itanium 2 processor, 4 GB of memory per processor).

Training and tutoring capacity

Jónsson has substantial experience in the supervision and tutoring of graduate students and post-docs (having been advisor to 10 post-docs and 14 Ph.D. students), including 3 RTN post-docs. Jónsson has also taught several courses at the MSc/ PhD level such as quantum mechanics for chemistry and solid state calculations. He is is now organizing a summer school with the title of "New Materials for the Hydrogen Economy" which will be held in Iceland in the summer of 2006. The presence of several Ph.D. students and post-docs in the group already performing research on production and storage of hydrogen will facilitate transfer of knowledge to the ESR and ER that will join the group.

Experience with international collaboration

Jónsson is a member of the Research Training Network "Predicting catalysis" of which Kroes, Nørskov, and Clary are also partners, and which will end in June 2006. The old network focuses on catalysis for ammonia production, which is intimately linked with hydrogen production. In fact, the Jónsson and Nørskov groups are already collaborating on a theoretical investigation of hydrogen formation at Pt and Ru electrodes as part of that Network. Concepts relevant to heterogeneous catalysis will also play an important role in our new research on hydrogen. Of the current PIs, Jónsson already collaborates with Kroes, Clary and Nørskov.

Key publications

  • G. Henkelman, A. Arnaldsson and H. Jónsson, Theoretical calculations of CH4 and H2 associative desorption from Ni(111): Could subsurface hydrogen play an important role? J. Chem. Phys. (in press 2006).
  • L. Xu, G. Henkelman, C. Campbell and H. Jónsson, Small Pd clusters, up to the tetramer at least, are highly mobile on the MgO(100) surface, Phys.Rev.Lett. 95, 146103 (2005).
  • R.M. Van Ginhoven, H. Jónsson, K.A. Peterson, M. Dupuis, and L. R. Corrales, An ab initio study of self-trapped excitons in alpha-quartz, J.Chem.Phys. 118, 6582 (2003).


References

27. K. Tsemekhman, E. Brown, E. Bylaska, and H. Jønsson, Phys.Rev.Lett. submitted (2006).
47. H. Jónsson, G. Mills, and K.W. Jacobsen, in Classical and quantum dynamics in condensed phase simulations, edited by B. J. Berne, G. Ciccotti and D. F. Coker (World Scientific, 1998).
57. G. Henkelman and H. Jónsson, J.Chem.Phys. 111, 7010 (1999).
74. G. Henkelman, B. Uberuaga, and H. Jonsson, J.Chem.Phys. 113, 9901 (2000).
75. G. Henkelman and H. Jónsson, J.Chem.Phys. 113, 9978 (2000).
76. G.H. Jóhannesson and H. Jónsson, J. Chem. Phys. 115, 9644 (2001).
77. T. Bligaard and H. Jónsson, Comp. Phys. Commun. 169, 284 (2005).
78. G. Mills, G.K. Schenter, D.E. Makarov, and H. Jónsson, Chem.Phys.Lett. 278, 91 (1997).
79. G. Henkelman and H. Jónsson, Phys.Rev.Lett. 90, 116101 (2003).
80. J. Song, R. vanGinhoven, L.R. Corrales, and H. Jónsson, Faraday Discuss. 303, 117 (2000).
81. J. Song, L.R. Corrales, G. Kresse, and H. Jónsson, Physical Review B 64, 134102 (2001).

11/11/2010