Nuclear magnetic resonance study on low-dimensional antiferromagnetic oxides: VOMoO4 and (V0.56Mo0.44)(2)O-5

Citation
S. Takata et al., Nuclear magnetic resonance study on low-dimensional antiferromagnetic oxides: VOMoO4 and (V0.56Mo0.44)(2)O-5, J PHYS JPN, 70(4), 2001, pp. 1124-1127
Citations number
9
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
ISSN journal
0031-9015 → ACNP
Volume
70
Issue
4
Year of publication
2001
Pages
1124 - 1127
Database
ISI
SICI code
0031-9015(200104)70:4<1124:NMRSOL>2.0.ZU;2-U
Abstract
We have carried out the nuclear magnetic resonance (NMR) of V-51 in VOMoO4, which contains linear chains of distorted VO6 octahedra. The temperature d ependence of the resonance shift K shows a small extremum around 100 K, tha t can reasonably be compared with the Bonner-Fisher-type behavior of the su sceptibility chi. V-51 relaxation rate T-1(-1), on the other hand, has a co mplex temperature dependence: an exponential decrease down to similar to 10 0K, a near plateau between similar to 100 and similar to 34 K and a monoton ous decrease below similar to 34 K. These are interpreted in terms of therm al-excitations between split t(2g) orbitals in energy (DeltaE similar to 68 0 K) due to the local distortion of VO6 octahedra at high temperatures, one -dimensional d-spin fluctuations, and a short-range magnetic ordering at lo w temperatures, respectively. It is noted that the change in the a-axis len gth must be taken into consideration to adequately describe the broad maxim um observed in both K and X around 100 K. The V-51 NMR in the related oxide (V0.56Mo0.44)(2)O-5 was also carried out, in which the VO6 and MoO6 octahe dra form a planer network sharing the corner oxygen atoms.