Abstract
We present a systematic study on hydrogenated silicon vacancies above saturation. For each system a global geometry optimization search for low-lying local minima is performed using a newly developed SiH tight binding model. Subsequently a large number of low-energy structures are examined by density functional calculations using a minimal basis set. Finally the energetically favorable structures are reexamined using a systematically extendable basis set with local, semilocal, and hybrid exchange-correlation functionals. Particular attention is paid to the divacancy to which the Raman peak at 3822 associated with the molecule had previously been assigned. Both the energetics and vibrational analysis of divacancy-related stable configurations suggest a revision of the above conclusion.
1 More- Received 18 March 2014
- Revised 11 August 2014
DOI:https://doi.org/10.1103/PhysRevB.90.054117
©2014 American Physical Society