物理化学学报 >> 2011, Vol. 27 >> Issue (01): 25-31.doi: 10.3866/PKU.WHXB20110123

热力学,动力学和结构化学 上一篇    下一篇

组氨酸12-硅钨杂多酸盐超分子化合物的结构与光致变色性质

孙德慧1, 张吉林2, 孙德新3   

  1. 1. 长春工程学院理学院, 长春130012;
    2. 中国科学院长春应用化学研究所, 稀土资源利用国家重点实验室, 长春130022;
    3. 装甲兵技术学院, 长春130117
  • 收稿日期:2010-07-23 修回日期:2010-10-21 发布日期:2010-12-31
  • 通讯作者: 孙德慧 E-mail:dhsun998@gmail.com
  • 基金资助:

    国家自然科学基金(20871083)资助项目

Structure and Photochromic Properties of a Histidine Salt of 12-Silicotungstate Supramolecular Compound

SUN De-Hui1, ZHANG Ji-Lin2, SUN De-Xin3   

  1. 1. Faculty of Science, Changchun Institute of Technology, Changchun 130012, P. R. China;
    2. State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China;
    3. The Amour Technology Institute of PLA, Changchun 130117, P. R. China
  • Received:2010-07-23 Revised:2010-10-21 Published:2010-12-31
  • Contact: SUN De-Hui E-mail:dhsun998@gmail.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20871083).

摘要:

通过溶液法合成了一个新颖的组氨酸12-硅钨杂多酸盐((HisH2)2SiW12O40·6H2O)单晶超分子化合物. 利用元素分析、热重-差热分析和X射线单晶衍射测试分别对其组成、热稳定性和结构进行了表征. 实验结果表明:该超分子化合物的组成为C12H34N6O50SiW12. 空气中, 在135 °C以下稳定. 它属于单斜晶系(空间群为C2/c), 晶胞参数为a=2.44005(18) nm, b=1.29788(10) nm, c=1.86898(14) nm, β=124.0380(10)°, V=4.9048(6) nm3,Z=4 和Dc=4.465 g·cm-3. 基于F2的最终统计: 拟合优度(GOF)=1.268, R1=0.0344 和wR2=0.0851 (I>2σ(I)). 该单晶超分子化合物的基本结构单元由一个[SiW12O40]4-多阴离子和两个质子化的[H2His]2+有机阳离子以及结晶水组成. 他们之间通过氢键的作用组装成三维网络结构. 在紫外光照射下, 样品具有光致变色性质. 通过对变色样品电子自旋共振谱的分析, 我们提出了一个可能的光致变色机理.

关键词: 超分子化合物, 多金属氧酸盐, 组氨酸, 光致变色

Abstract:

We synthesized a novel histidine salt of 12-silicotungstate supramolecular compound ((HisH2)2SiW12O40·6H2O) by a solution method. Its composition, thermostability, and structure were characterized by elemental analysis, thermal gravimetric and differential thermal analysis (TG-DTA), and single crystal X-ray diffraction, respectively. The experimental results show that the supramolecular compound has a composition of C12H34N6O50SiW12 and it is stable under 135 °C in air. It belongs to a monoclinic system (space group C2/c) with a=2.44005(18) nm, b=1.29788(10) nm, c=1.86898(14) nm, β=124.0380(10)°, V= 4.9048(6) nm3, Z=4, and Dc=4.465 g·cm-3. The final statistics based on F2 are goodness-of-fit (GOF) = 1.268, R1=0.0344 and wR2=0.0851 for (I>2σ(I)). X-ray diffraction analysis further reveals that this supramolecular compound mainly consists of polyoxometalate anions [SiW12O40]4-, protonated histidine cations [HisH2]2+ and lattice water. A three-dimensional (3D) network is formed through hydrogen bonding. The resulting sample shows photochromism under UV irradiation. We propose a possible photochromic mechanism by an analysis of the chromic sample′s electron spin resonance (ESR) spectrum.

Key words: Supramolecular compound, Polyoxometalate, Histidine, Photochromism