Abstract

51V-NMR experiments have been performed to investigate the local magnetic and electronic properties of the mixed-valence oxide δ-Ag2/3V2O5, which shows the novel V4+/V5+ charge ordering trigged by Ag ion ordering. We have observed the abrupt loss of 51V-NMR signal coming from the non-magnetic V5+-like ions above Tc = 225 K. It indicates that the majority of V ions are magnetic above Tc and that the phase transition is accompanied by the charge separation and the charge ordering of 3d electrons on V sites. In the low-temperature phase below Tc, the nuclear spin-lattice relaxation rate 1/T1 shows the thermal activation-type temperature dependence with the activation energy of about 130 K. It has been clarified that the ground state of this material is the charge ordered one with the spin singlet of 3d electrons on V4+-V4+ pair from a microscopic point of view.

Details

Title
51V-NMR study of charge order induced by cation order in δ-Ag2/3V2O5
Author
Kawasaki, Y 1 ; Morioka, R 1 ; Kishimoto, Y 1 ; Nakamura, K 1 ; Nishiyama, K 2 ; Koyama, T 2 ; Mito, T 2 ; Baba, T 3 ; Yamauchi, T 3 ; Isobe, M 4 ; Ueda, Y 5 

 Graduate School of Science and Technology, Tokushima University, Tokushima 770-8506, Japan 
 Graduate School of Material Science, University of Hyogo, Hyogo 678-1297, Japan 
 Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan 
 Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany 
 Toyota Physical and Chemical Research Institute, Nagakute, Aichi 480-1192, Japan 
Publication year
2017
Publication date
Apr 2017
Publisher
IOP Publishing
ISSN
17426588
e-ISSN
17426596
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2573838431
Copyright
© 2017. This work is published under http://creativecommons.org/licenses/by/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.