CAN CONFORMATIONAL EQUILIBRIA BE TUNED IN SUPERCRITICAL-FLUID SOLUTION - AN IR SPECTROSCOPIC STUDY OF TRANS/GAUCHE ISOMERISM OF HEXAFLUOROPROPAN-2-OL IN SUPERCRITICAL SF6 AND CHF3 SOLUTIONS

被引：13

作者：

KAZARIAN, SG ^{[1
]}

POLIAKOFF, M ^{[1
]}

机构：

[1] UNIV NOTTINGHAM,DEPT CHEM,NOTTINGHAM NG7 2RD,ENGLAND

来源：

JOURNAL OF PHYSICAL CHEMISTRY | 1995年 / 99卷 / 21期

关键词：

D O I：

10.1021/j100021a028

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：

We report the effect of fluid density and polarity on the trans reversible arrow gauche equilibrium of the rotamers of (CF3)(2)CHOH in supercritical SF6 (scSF(6)) and CHF3 (scCHF(3)) solutions. The equilibrium is followed by IR spectroscopy in the nu(O-H) region (3700-3500 cm(-1)). An unusual aspect is the use of long and short path length IR cells in tandem to circumvent problems of IR absorption by the fluids. A comparison of the effects of increasing pressure in the nonpolar fluid scSF(6) and the polar fluid scCHF(3) allows us to separate the effect of increasing density, which happens to be small, and the effect of increasing dielectric constant, which favors the gauche rotamer. The change in equilibrium constant for trans = gauche is correlated to the polarity of the fluid via the Kirkwood parameter.

引用

页码：8624 / 8628

页数：5

共 47 条

[1] ROTATIONAL ISOMERISM .2. A CALCULATION OF SOLVENT DEPENDENCE OF CONFORMATIONAL EQUILIBRIA IN SUBSTITUTED ETHANES AND ITS APPLICATION TO NMR SPECTRA [J].