https://doi.org/10.1140/epjb/e2003-00072-0
Magnetic susceptibility in quasi one-dimensional Ba2V3O9: chain segmentation versus the staggered field effect
1
Max Planck Institute for the Chemical Physics of Solids, Nöthnitzer Strasse 40, 01187 Dresden, Germany
2
Joint Institute for Nuclear Research, Dubna, Russia
3
Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
Corresponding author: a bs@cpfs.mpg.de
Received:
19
December
2002
Revised:
29
January
2003
Published online:
14
March
2003
A pronounced Curie-like upturn of the magnetic susceptibility
of the quasi one-dimensional spin chain compound
Ba2V3O9 has been found recently [CITE].
Frequently this is taken as a signature for a staggered field
mechanism due to the presence of g-factor anisotropy and
Dzyaloshinskii-Moriya interaction. We calculate this contribution
within a realistic structure of vanadium 3d- and oxygen
2p-orbitals and conclude that this mechanism is far too small to
explain experimental results. We propose that the Curie term is
rather due to a segmentation of spin chains caused by broken
magnetic bonds which leads to uncompensated
spins
of segments with odd numbers of spins. Using the finite-temperature
Lanczos method we calculate their effective moment and show that
of broken magnetic bonds is sufficient to reproduce
the anomalous low-T behavior of
in Ba2V3O9.
PACS: 75.10.Jm – Quantized spin models / 75.40.Cx – Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.) / 75.50.Ee – Antiferromagnetics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003