Effect of ionic equilibria on redox potentials in supercritical difluoromethane

被引：12

作者：

Abbott, AP ^{[1
]}

Durling, NE ^{[1
]}

机构：

[1] Univ Leicester, Dept Chem, Leicester LE1 7RH, Leics, England

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2001年 / 3卷 / 04期

关键词：

D O I：

10.1039/b008552i

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The equilibrium constants for the dissociation of ferrocene carboxylic acid and the tetrabutyl ammonium salt have been determined in supercritical (sc) difluoromethane (HFC32). It is shown that the redox potential of ferrocene is largely unaffected by changes in pressure whereas the redox properties of ferrocence derivatives vary significantly. The changes in the oxidation potential are related to the dissociation constants of the electroactive species using classical equilibrium thermodynamics. Deviations from Nernstian redox behaviour are interpreted in terms of a decrease in the activity coefficient of the ferrocene derivatives at high pressure. The results also suggest that ionic atmosphere effects are insignificant in sc fluids like difluoromethane at lower pressures due to low ionic strengths and high ionic mobilities.

引用

页码：579 / 582

页数：4

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