Structural characterization and ferroelectric ordering in (C3N2H5)5Sb2Br11 |
| |
Authors: | A Piecha G Bator |
| |
Institution: | a Faculty of Chemistry, University of Wroc?aw, Joliot-Curie 14, 50-383 Wroc?aw, Poland b Institute of Low Temperature and Structure Research, Polish Academy of Science, Okólna 2, 50-950 Wroc?aw 2, PO Box 937, Poland |
| |
Abstract: | A ferroelectric crystal (C3N2H5)5Sb2Br11 has been synthesized. The single crystal X-ray diffraction studies (at 300, 155, 138 and 121 K) show that it is built up of discrete corner-sharing bioctahedra and highly disordered imidazolium cations. The room temperature crystal structure has been determined as monoclinic, space group, P21/n with: , and and β=96.19°. The crystal undergoes three solid-solid phase transitions: ) discontinuous, continuous and discontinuous. The dielectric and pyroelectric measurements allow us to characterize the low temperature phases III and IV as ferroelectric with the Curie point at 145 K and the saturated spontaneous polarization value of the order of along the a-axis (135 K). The ferroelectric phase transition mechanism at 145 K is due to the dynamics of imidazolium cations. |
| |
Keywords: | 77 80 &minus e 77 70 _method=retrieve& _eid=1-s2 0-S0022459608001047& _mathId=si135 gif& _pii=S0022459608001047& _issn=00224596& _acct=C000053510& _version=1& _userid=1524097& md5=f95255f5685ef3436503a8ee82893417')" style="cursor:pointer +a" target="_blank">" alt="Click to view the MathML source" title="Click to view the MathML source">+a 61 10 &minus i |
本文献已被 ScienceDirect 等数据库收录! |
|