物理化学学报 >> 1992, Vol. 8 >> Issue (06): 783-788.doi: 10.3866/PKU.WHXB19920613

研究论文 上一篇    下一篇

四氯合铜酸二烷基铵相变的热分析和红外光谱

郭宁; 曾广赋; 席时权   

  1. 中国科学院长春应用化学研究所,长春 130022
  • 收稿日期:1991-07-08 修回日期:1992-02-24 发布日期:1992-12-15
  • 通讯作者: 曾广赋

Thermal Analysis nad Infrared Spectra of Dialkylammonium Tetrachlorocuprate

Guo Ning; Zeng Guang-Fu; Xi Shi-Quan   

  1. Changchun Institute of Applied Chemistry, Academia Sinica, Changchun 130022
  • Received:1991-07-08 Revised:1992-02-24 Published:1992-12-15
  • Contact: Zeng Guang-Fu

摘要: 用DSC和TG研究了(n-C_nH_(2n+1)NH_3)_2CuCl_4(n=7-12)(记为C_nM)配合物的热稳定性和固-固相变。由红外光谱讨论了C_9Cu三个相的性质。发现C_nM的热稳定性呈奇偶效应; 主相变峰温随链长增长而升高; 相变总ΔH和ΔS也随链增长而加大; 当n≤9时, 高温相为部分无序相; 而n≤10时, 高温相为构象无序相。C_9Cu的主相变主要源自链间堆积结构变化。而在307.7 K的相变主要与烃链有序-无序变化有关。

关键词: 热分析, 红外光谱, 相变, 热稳定性, 有序-无序

Abstract: The thermal stability and the solid-solid phase transitions in the [n-C_nH_(2n+1)NH_3]_2CuCl_4 compounds with n=7-12 have been studied by DSC and TG methods. Comparision with C_nZn compounds was made. The nature of three phases of C_9Cu has been discussed in terms of infrared spectroscopy and the assignment of the phase transitions has been given. The thermal stability of C_nCu is lower than that of C_nZn and presents an obvious odd-even effect. All of these compounds exhibit two solid-solid phase transitions in the temperature range of 248-337 K. The peak temperature of phase transitions changes regularly. The peak temperature of the main phase transition increases with the chain length. The total transition enthalpies and entropies increase with increasing chain length. When n≤9, the high temperature phase exists in a partial disorder state. When n≥10, the high temperature phase exists in a conformational disorder state. The main phase transition and the phase transition at 307.7 K of C_9Cu may mainly arise from the change of the packing structure and the change of the partial conformational order-disorder of alkyl chain, respectively.

Key words: Thermalanalysis, Infrared spectroscopy, Phase transition, Order-disorder, Thermal stability