Acta Chimica Sinica ›› 2021, Vol. 79 ›› Issue (1): 119-125.DOI: 10.6023/A20080397 Previous Articles     Next Articles


{(Me2NH2)2[Fe2(ox)2Cl4]•H2O} n (ox=oxalate)中客体水分子诱导的介电弛豫行为

王宾a, 唐雯a, 赵海霞a,*(), 龙腊生a,*(), 郑兰荪a   

  1. a 厦门大学 化学化工学院化学系 固体表面物理化学国家重点实验室 能源材料化学协同创新中心 厦门 361005
  • 投稿日期:2020-08-29 发布日期:2020-10-20
  • 通讯作者: 赵海霞, 龙腊生
  • 作者简介:
    These authors contributed equally to this work.
  • 基金资助:
    国家自然科学基金(21431005); 国家自然科学基金(21721001); 国家自然科学基金(21571150)

Dielectric Relaxation Triggered by Guest Water Molecule Based on the {(Me2NH2)2[Fe2(ox)2Cl4 ]•H2 O}n(ox=oxalate)

Bin Wanga, Wen Tanga, Haixia Zhaoa,*(), Lasheng Longa,*(), Lansun Zhenga   

  1. a Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
  • Received:2020-08-29 Published:2020-10-20
  • Contact: Haixia Zhao, Lasheng Long
  • Supported by:
    the National Natural Science Foundation of China(21431005); the National Natural Science Foundation of China(21721001); the National Natural Science Foundation of China(21571150)

It is well known that water is one of the most important chemical constituent in the nature, and thus is regarded as the genesis of life. Meanwhile, water plays an irreplaceable role in biology process, such as regulating the affinity between fatty acids and alkyl chains and controlling the conformation of DNA. In the crystal chemistry, water molecules in compounds will also significantly affect its structure, physical and chemical properties. Among them, single crystal to single crystal (SCSC) transformations induced by water molecules have attracted great attention, because those transformations often change the physical properties such as magnetic, dielectric and proton conduction. More importantly, it is facile to obtain detailed structural information, which leads to more directly and better understanding the transformation mechanism and structure-properties relationship. In this work, we report the SCSC transformation in the compound of {(Me2NH2)2- [Fe2(ox)2Cl4]•H2O} n (ox=oxalate) ( 1•H2O), which was prepared through the hydrothermal reaction of oxalate and FeCl3 in the presence of dimethylamine chloride. Under vacuum and heating conditions, 1•H2O underwent SCSC transformations, formed compound 1. 1•H2O and 1 were characterized by X-ray single-crystal diffraction, powder X-ray diffraction, magnetic, dielectric and thermogravimetric analysis. Magnetic studies on 1•H2O and 1 show that the presence or absence of guest water molecules had no significant effect on their magnetic interaction. Investigation on the dielectric properties of 1•H2O and 1 reveals that the presence of guest water molecules can influence the dynamic relaxation process of guest amine and water in the compound. Compound 1•H2O exhibited three dielectric relaxations at 250 K, 80 K and 50 K respectively, while 1 only showed a single relaxation process at 80 K. This work sheds light on the further exploration of SCSC transformations associated with the dielectric relaxation.

Key words: dielectric relaxation, SCSC structural transformation, water, magnetism