Structural Assignment of Polarization in Hydrogen-Bonded Supramolecular Ferroelectrics

详细信息    查看全文

• 作者：Reiji Kumai ; Sachio Horiuchi ; Hajime Sagayama ; Taka-hisa Arima ; Masashi Watanabe ; Yukio Noda ; Yoshinori Tokura
• 刊名：Journal of the American Chemical Society
• 出版年：2007
• 出版时间：October 31, 2007
• 年：2007
• 卷：129
• 期：43
• 页码：12920 - 12921
• 全文大小：92K
• 年卷期：v.129,no.43(October 31, 2007)
• ISSN：1520-5126

文摘

A 1:1 adduct of phenazine (Phz) with chloranilic acid (H₂ca) and bromanilic acid (H₂ba), in which nonpolar neutral molecules are connected by the intermolecular O-H···N hydrogen bonds, shows ferroelectric transitions. Neutron diffraction analysis of these materials reveals that there are two inequivalent hydrogen-bonding sites below the ferroelectric transition temperature (253 K for Phz-H₂ca and 168 K for Phz-H₂ba). This asymmetry was also observed by the maximum entropy method (MEM) analysis of the synchrotron X-ray diffractions. The structure analysis results suggest that the origin of the polarization of the material is the symmetry breaking based on the two inequivalent hydrogen bonds.