Acta Phys. -Chim. Sin. ›› 2009, Vol. 25 ›› Issue (10): 1945-1950.doi: 10.3866/PKU.WHXB20091001

• ARTICLE • Previous Articles     Next Articles

Synthesis and Thermochemical Properties of New Ternary Lanthanum Complex La(Glu)(Im)6(ClO4)3·4HClO4·4H2O

LV Xue-Chuan, TAN Zhi-Cheng, GAO Xiao-Han   

  1. School of Chemistry and Material Science, Liaoning Shihua University, Fushun 113001, Liaoning Province, P. R. China|Thermochemistry Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, P. R. China|China Ionic Liquid Laboratory, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning Province, P. R. China
  • Received:2009-05-13 Revised:2009-06-23 Published:2009-09-29
  • Contact: TAN Zhi-Cheng E-mail:tzc@dicp.ac.cn

Abstract:

A new ternary lanthanum complex, La (Glu) (Im)6 (ClO4)3·4HClO4·4H2O (Glu: glutamic acid, Im: imidazole), was synthesized and its thermodynamic properties were studied. Heat capacities of the complex were measured with a high-precision automatic adiabatic calorimeter over a temperature range from 80 to 390 K and the thermodynamic functions (HT-H298.15) and (ST-S298.15) were derived from the heat capacity data with a temperature interval of 5 K. Glass and phase transitions of the new complex at around 216 and 246 K were observed both by adiabatic calorimetry and differential scanning calorimetry (DSC) analyses. Thermodynamic data of the phase transitions were calculated and the transition mechanism was determined to be a re-orientational process of the perchlorate ions in the complex. The thermal stability of the complex was tested by the thermogravimetric (TG) technique and a possible mechanism for its decomposition was proposed.

Key words: Heat capacity, La(Glu)(Im)6(ClO4)3·4HClO4·4H2O, Adiabatic calorimetry, Thermodynamic function, Phase transition, Thermal stability

MSC2000: 

  • O642.3