Wuhan University Journal of Natural Sciences

, Volume 5, Issue 4, pp 479–484 | Cite as

Study of complexes of lanthanum with amino acids by titration calorimeter

  • Ye Gang
  • Wang Cun-xin
  • Qu Song-sheng


The stability constants and thermodynamic functions for complexes of lanthanum with eight kind of amino acids according to 1∶1 and 1∶2 in proportion have been determined by titration calorimeter at 298.15 K. The enthalpy change makes a predominant contribution to the stability of these complexes. The ring in amino acid associated with lanthanum ion helps to enhance the stability of complexes. Steric effects between rings in complexes leads to that the equilibrium constants of reaction of the complexes (1∶2) is much less than that of the complexes (1∶1).

Key words

titration calorimeter rare earth amino acid complexes steric effects 

CLC number

O 642.3 


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  1. [1]
    Jin Tian-zhu, Yang Chang-qing, Yang Qing-chuan,et al. Studies on Rare Earth Complexes of Amino Acids (1)-Synthesis and Crystal Structure of Triglycinato-diaquo-praseodyminum Chlorides.Chem J Chinese Universities, 1989,10(2): 118(Ch).Google Scholar
  2. [2]
    Den Nu-wen, Wu Ji-gui, Zhu Yuan-chen. Studies on Binary and Ternary Complex of Alanine with Rare Earth Ions by pH Potentiometric Method.Chem J Chinese Universities, 1991,7: 853(Ch).Google Scholar
  3. [3]
    Zhang Ya-fei, Niu chun-ji, Ni Jia-zuan. Thermodynamic Property of Complexes of Rare Earth with L-threonine.J Chinese Rare Earth Society, 1992,10(3): 207(Ch).Google Scholar
  4. [4]
    Christensen J J, Wrathall D P, Izatt R M. Calorimetric Determination of lgK, ΔH, and ΔS from Thermometric Titration Data.Anal Chem, 1968,40: 175.CrossRefGoogle Scholar
  5. [5]
    Huang Ying-jun, Wang Chun-xing, Qu Song-sheng,et al. Development of a Titration Calorimeter.J Wuhan Univ (Nat Sci Ed), 1994,40(6): 76(Ch).Google Scholar
  6. [6]
    Bates R G, Hetzerh B. Dissociation Constant of the Protonated Acid Form of 2-amino-2-(hydroxymethyl)-1,3-propanediol[tris-hydroxymethyl-aminomethane] and Related Thermodynamic Quantities from 0 to 50°C.J Phys Chem, 1961,65: 667.CrossRefGoogle Scholar
  7. [7]
    Huang Xi-rong, Jiang Ben-gao, Yin Jing-zhi,et al. Thermodynamics Properties of Rare Earth(III)-crownether Coordination Reactions(II).ACTA Chimica sinica, 1991,49: 359(Ch).Google Scholar
  8. [8]
    Dean J A.Lange's Handbook of Chemistry. Translated by Shang Fang-jiu,et al. Beijing: Science Press, 1991. 2(Ch).Google Scholar
  9. [9]
    Philip M, Peerzada M P, Joshi J D. Formation Constants of Lanthanide Complexes with Some Amino Acids.J Indian Chem Soc, 1987,64: 436.Google Scholar
  10. [10]
    Rodante F. Thermodynamics of the “standard” α-amino Acids in Water at 25°C.Thermochimica Acta, 1989,149: 157.CrossRefGoogle Scholar
  11. [11]
    Sekhon B S, Chopra S L. Stability Constants of Lanthanum(III) Complexes with Threonine and Hydroxyproline.Ann Chim, 1975,10: 21.Google Scholar
  12. [12]
    Su Qian.Rare Earth Chemistry. Zhengzhou: Henan Science Press, 1993. 125(Ch).Google Scholar

Copyright information

© Springer 2000

Authors and Affiliations

  • Ye Gang
    • 1
  • Wang Cun-xin
    • 1
  • Qu Song-sheng
    • 1
  1. 1.College of Chemistry and Environment ScienceWuhan UniversityWuhanChina

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