Eur. Phys. J. D 45, 471-476 (2007)
https://doi.org/10.1140/epjd/e2007-00166-9

Optical properties of small silver clusters supported at MgO

¹ Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Straße 2, 12489 Berlin, Germany
² Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel

Corresponding author: ^a vbk@chemie.hu-berlin.de

Received: 24 January 2007
Revised: 3 April 2007
Published online: 23 May 2007

Abstract

We present structural and optical properties of silver clusters Ag_n (n=2, 4, 6, 8) at two model support sites of MgO, stoichiometric MgO(100) and F_S-center defect, based on density functional theory and embedded cluster model. Our results provide the mechanism responsible for the absorption and emission patterns due to the specific interaction between the excitations within the cluster and the support site which is strongly cluster size and structure dependent. We propose Ag₄ at stoichiometric site as well as Ag₂, Ag₄ and Ag₆ at F_S-center defects as good candidates for the emissive centers in the visible regime.