https://doi.org/10.1007/s100510050455
A new view of the electronic structure of the spin-Peierls compound NaV2O5 *
Max-Planck-Institut für Festkörperforschung,
Heisenbergstrasse 1, 70569 Stuttgart, Germany
Corresponding author: a horsch@audrey.mpi-stuttgart.mpg.de
Received:
28
January
1998
Accepted:
17
March
1998
Published online: 15 October 1998
The present understanding of the electronic and magnetic properties of
-NaV2O5 is based on the hypothesis of strong charge
disproportionation into V4+ and V5+, which is assumed to lead
to a spin-1/2 Heisenberg chain system.
A recent structure analysis shows, however, that the V-ions are in a mixed
valence state and indistiguishable. We propose an explanation for
the insulating state, which is not based on charge modulation, and
show that strong correlations together with
the Heitler-London character of the relevant intermediate
states naturally lead to antiferromagnetic Heisenberg chains.
The interchain coupling is weak and frustrated, and its effect on the
uniform susceptibility is found to be small.
PACS: 75.50.Ee – Antiferromagnetics / 75.30.Et – Exchange and superexchange interactions / 75.40.Cx – Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998