Ab initio study of icosahedral Al-Pd-Mn quasicrystals: Structural model, electric field gradients, and negative valence of Mn

E. S. Zijlstra, S. K. Bose, M. Klanjšek, P. Jeglič, and J. Dolinšek
Phys. Rev. B 72, 174206 – Published 22 November 2005

Abstract

The atomic and electronic structures of the Quandt-Elser model of iAl70.8Pd21.5Mn7.7 [A. Quandt and V. Elser, Phys. Rev. B 61, 9336 (2000)] are studied by pseudopotential and full-potential linear augmented plane-wave methods. A model with a lower total energy than the original Quandt-Elser model (ΔE=0.03eV/atom) is obtained by moving one of the Al atoms on a cube in the Mackay void away from its high symmetry position and by performing a subsequent structural relaxation. The electronic density of states of this modified Quandt-Elser model is found to be similar to that of the model of Katz and Gratias, but with a more pronounced pseudogap near the Fermi energy. Good agreement is obtained with an available photoemission spectrum, but calculated electric field gradients do not reproduce the angular dependence of a Al27 nuclear magnetic resonance spectrum. By introducing vacancies at Mn sites and by comparing the filling of bands near the Fermi energy for the models with and without a vacancy, it is found that the Mn atoms have an apparent negative number of 3.2 valence electrons independent of the Mn site. It is argued that this apparent negative number of valence electrons is due to the filling of Mnd states below the Fermi energy.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
1 More
  • Received 6 July 2005

DOI:https://doi.org/10.1103/PhysRevB.72.174206

©2005 American Physical Society

Authors & Affiliations

E. S. Zijlstra* and S. K. Bose

  • Department of Physics, Brock University, St. Catharines, Ontario Canada L2S 3A1

M. Klanjšek, P. Jeglič, and J. Dolinšek

  • J. Stefan Institute, University of Ljubljana, Jamova 39, SI-1000 Ljubljana, Slovenia

  • *Electronic address: EZijlstr@brocku.ca

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 72, Iss. 17 — 1 November 2005

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×