title: Influence of the incommensurability in Sr14-xCaxCu24O41 Family Compounds.
abstract: We study the influence of the structural modulation on the low energy physics of the Sr14-xCaxCu24O41 oxides, using ab initio determination of the on-site and nearest-neighbor effective parameters. The structural modulations appear to be the key degree of freedom responsible for the low energy properties, such as the electron localization, the formation of dimers in the x=0 compound, or the antiferromagnetic order in the x=13.6 compound.
authors.affiliation: Laboratoire de Physique Quantique, IRSAMC/UMR 5626, Université Paul Sabatier, 118 route de Narbonne, F-31062 Toulouse Cedex 4, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Gellé
authors.forename: Marie-Bernadette
authors.initials: MB
authors.lastname: Lepetit