https://doi.org/10.1140/epjd/e2012-30071-y
Regular Article
A study of color centers in MgO using a hierarchical model
1
Institut für Theoretische Physik II, Universität
Erlangen-Nürnberg, Staudstr.
7, 91058
Erlangen,
Germany
2
Laboratoire de Physique Théorique, Université P.
Sabatier, 118 route de
Narbonne, 31062
Toulouse Cedex,
France
a
e-mail: paul-gerhard.reinhard@physik.uni-erlangen.de
Received: 27 January 2012
Received in final form: 16 April 2012
Published online: 29 June 2012
Neutral and charged color centers in MgO, both in bulk and at the surface, are investigated from a theoretical perspective. We use a hierarchical approach which combines quantum-mechanical description with molecular mechanics (QM/MM) taking care to include dynamical polarizability of the MgO substrate. The performance of the QM/MM approach is compared with ab-initio calculations and with experimental data where available. We obtain fair acceptable agreement which lies well in the span of the different predictions. The particular efficiency of the QM/MM approach allows to vary the system size more freely and so to test the impact of the (necessarily) finite sample. We find that the sampling size plays a crucial role for color centers at MgO surface because the surface deformation can extend over several grid points.
Key words: Topical issue: Atomic Cluster Collisions. Guest editors: Andrey V. Solov’yov and Andrey V. Korol
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2012
