Acta Phys. -Chim. Sin. ›› 2001, Vol. 17 ›› Issue (04): 343-347.doi: 10.3866/PKU.WHXB20010413

• ARTICLE • Previous Articles     Next Articles

Enthalpy and Entropy Criterion for the Molecular Recognize of Some Organic Compounds with Beta Cyclodextrin

Zheng Xiao-Ming;Lu Wei-Min;Sun De-Zhi   

  1. Institute of Catalysis,Xixi Campus,Zhejiang University,Hangzhou 310028;Department of Chemistry,Liaocheng Teachers′College,Liaocheng 252059
  • Received:2000-09-15 Revised:2000-12-14 Published:2001-04-15
  • Contact: Zheng Xiao-Ming

Abstract: Adsorption thermodynamic functions for some organic solvent molecules on the surface of beta cyclodextrin(β-CD)have been measured using gas chromatographic technique.The experimental results confirm thatβ-CD molecule can form hostguest adduct with adsorbate molecule(guest) as it can in aqueous solution and show that when there is a strong intermolecular force between the host and the guest a type of synergistic interaction exists between,the inner cave and some hydroxyl groups of the CD molecule simultaneously with the apolar/hydrophobic and the polar/hydrophilic parts of the guest molecule.The experimental results also show that a phenomenon of mutual compensation between enthalpy and entropy relates closely with molecular recognize and the sum of the absolute values of adsorption enthalpy and entropy could be considered as a criterion to differentiate intermolecular force of the recognize.

Key words: Molecular recognize, Beta cyclodextrin, Enthalpy, Entropy, Criterion