title: Materials physics: reactive walls.
authors.affiliation: Unit of Theoretical Materials Physics, Université de Liège, B-4000 Sart Tilman, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ghosez
authors.affiliation: Department of Condensed Matter Physics, Université de Genève, CH-1211 Geneva, Switzerland.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Triscone