Chris G. Van de Walle and Anderson Janotti
The Feature Article by Chris G. Van de Walle and Anderson Janotti (pp. 19–27) is the first contribution to a series of articles (in total 17 Feature Articles and an Expert Opinion) devoted to various aspects of theoretical studies of impurities and point defects in solids, which will be published in physica status solidi (b) during 2011. Guest edited by A. Alkauskas, P. Deák, J. Neugebauer, A. Pasquarello, and C. G. Van de Walle, the series “Advanced Calculations for Defects in Solids – Electronic Structure Methods” provides an overview of the current status of available methods, describes the limits of and necessary corrections to standard approaches used today, and evaluates various ways of going beyond them. The variety of approaches reflects the intrinsic difficulties that electronic structure methods need to overcome in this research area. The image on the front cover of this issue displays the charge density of the gap state of a neutral oxygen vacancy in ZnO, which is occupied with two electrons. The isosurface corresponds to 10% of the maximum.