First-principles study of the dynamic Jahn-Teller distortion of the neutral vacancy in diamond

Joseph C. A. Prentice, Bartomeu Monserrat, and R. J. Needs
Phys. Rev. B 95, 014108 – Published 20 January 2017
PDFHTMLExport Citation

Abstract

First-principles density functional theory methods are used to investigate the structure, energetics, and vibrational motions of the neutral vacancy defect in diamond. The measured optical absorption spectrum demonstrates that the tetrahedral Td point group symmetry of pristine diamond is maintained when a vacancy defect is present. This is shown to arise from the presence of a dynamic Jahn-Teller distortion that is stabilized by large vibrational anharmonicity. Our calculations further demonstrate that the dynamic Jahn-Teller-distorted structure of Td symmetry is lower in energy than the static Jahn-Teller distorted tetragonal D2d vacancy defect, in agreement with experimental observations. The tetrahedral vacancy structure becomes more stable with respect to the tetragonal structure by increasing temperature. The large anharmonicity arises mainly from quartic vibrations, and is associated with a saddle point of the Born-Oppenheimer surface and a minimum in the free energy. This study demonstrates that the behavior of Jahn-Teller distortions of point defects can be calculated accurately using anharmonic vibrational methods. Our work will open the way for first-principles treatments of dynamic Jahn-Teller systems in condensed matter.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 7 October 2016

DOI:https://doi.org/10.1103/PhysRevB.95.014108

©2017 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Joseph C. A. Prentice1, Bartomeu Monserrat1,2, and R. J. Needs1

  • 1TCM Group, Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
  • 2Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 95, Iss. 1 — 1 January 2017

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
×