title: Wigner crystallization in Na3Cu2O4 and Na8Cu5O10 chain compounds.
abstract: We report the synthesis of novel edge-sharing chain systems Na(3)Cu(2)O(4) and Na(8)Cu(5)O(10), which form insulating states with commensurate charge order. We identify these systems as one-dimensional Wigner lattices, where the charge order is determined by long-range Coulomb interaction and the number of holes in the d shell of Cu. Our interpretation is supported by x-ray structure data as well as by an analysis of magnetic susceptibility and specific heat data. Remarkably, due to large second neighbor Cu-Cu hopping, these systems allow for a distinction between the (classical) Wigner lattice and the 4k(F) charge-density wave of quantum mechanical origin.
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Horsch
authors.forename: M
authors.initials: M
authors.lastname: Sofin
authors.forename: M
authors.initials: M
authors.lastname: Mayr
authors.forename: M
authors.initials: M
authors.lastname: Jansen