title: Dynamical singlets and correlation-assisted Peierls transition in VO2.
abstract: A theory of the metal-insulator transition in vanadium dioxide from the high- temperature rutile to the low- temperature monoclinic phase is proposed on the basis of cluster dynamical mean-field theory, in conjunction with the density functional scheme. The interplay of strong electronic Coulomb interactions and structural distortions, in particular, the dimerization of vanadium atoms in the low-temperature phase, plays a crucial role. We find that VO2 is not a conventional Mott insulator, but that the formation of dynamical V-V singlet pairs due to strong Coulomb correlations is necessary to trigger the opening of a Peierls gap.
authors.affiliation: Centre de Physique Théorique, Ecole Polytechnique, 91128 Palaiseau Cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Biermann
authors.forename: A
authors.initials: A
authors.lastname: Poteryaev
authors.forename: A I
authors.initials: AI
authors.lastname: Lichtenstein
authors.forename: A
authors.initials: A
authors.lastname: Georges