Physical Review Letters Reports Progress on Ferroelectric Substance

Researchers from the National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, recently made new progress in the study over the charge ordering states in and spontaneous polarization of the electronic ferroelectric LuFe2O4. The research team led by Research Fellow Li Jianqi reveals that ferroelectric LuFe2O4 has a curious ground state distinguished by electron stripes, in which the charge-density wave behavior in a nonsinusoidal fashion results in elemental electric dipoles for ferroelectricity. Researchers discovered that these electron stripes manifest a frustrated charge density wave with a remarkable ferroelectric polarization. This 3-dimensional charge ordering state, occurring at a low temperature of about 20K, was directly revealed for the first time by their in-situ transmission electron microscopy (TEM). The feat was reported on the June 15th issue of Physical Review Letters (Phys. Rev. Lett. 98 (2007)247602).

Feat on a Zinc-Zinc Bond Compound Selected by NatureChina as Highlight

The first organometallic compound with a zinc–zinc (Zn–Zn) bond was isolated and identified in 2004. So far, only a few samples of this kind have been reported as compound, which is of significant for the research on the metal bonding theory, materials science and catalytic action, is extremely sensitive to the air and needs rigorous reaction conditions. Recently, a research from the National Engineering Research Center for Fine Petrochemical Intermediates, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, reported the synthesis and structure of a Zn–Zn-bonded compound. The paper entitled “A new zinc-zinc-bonded compound with a dianionic -diimine ligand: synthesis and structure of [Na(THF)2]2 [LZn-ZnL] (L = [(2,6-iPr2C6H3)N(Me)C]22-)” was published on the inside front cover of ChemComm (Chem. Commun. 2007, 2363-2365). On May 9, the feat was selected as this week's research highlights from NatureChina, dedicated to highlighting the best research from mainland China and Hong Kong. Nature China is the latest online journal run by the U.K.-based Nature Publishing Group.

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