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Updated: May 28, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Possible spin singlet quadrumerization in Pb2Re2O(7-δ)
C Michioka1, Y Kataoka, H Ohta
1Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan. michioka@kuchem.kyoto-u.ac.jp
Abstract:
A single crystal of pyrochlore Pb(2)Re(2)O(6.75) was prepared by hydrothermal synthesis, and its magnetic and transport properties were investigated. Pb(2)Re(2)O(6.75) shows the metallic conduction with an anomalous second-order structural phase transition at T(s)=294 K, in which the magnetization and the structure change similarly to that at 200 K of the superconductor Cd(2)Re(2)O(7). A three-dimensional Ising-like order parameter probed by the atomic displacement suggests that an unconventional spin singlet state is possibly realized in the ground state of Pb(2)Re(2)O(6.75), in which four spins make a quadrumer in order to remove the spin frustration of the pyrochlore lattice.
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