The Cybotactic Region Surrounding Fluorescent Probes Dissolved in 1-Butyl-3-methylimidazolium Hexafluorophosphate: Effects of Temperature and Added Carbon Dioxide
| Autor: | Frank V. Bright, Sheila N. Baker, and Maureen A. Kane, Gary A. Baker |
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| Rok vydání: | 2001 |
| Předmět: |
1-Butyl-3-methylimidazolium hexafluorophosphate
Analytical chemistry Activation energy Dielectric Mole fraction Fluorescence Surfaces Coatings and Films chemistry.chemical_compound chemistry Hexafluorophosphate Ionic liquid Materials Chemistry Organic chemistry Physical and Theoretical Chemistry Bar (unit) |
| Zdroj: | The Journal of Physical Chemistry B. 105:9663-9668 |
| ISSN: | 1520-5207 1520-6106 |
| Popis: | We report on the local microenvironment that surrounds three fluorescent solutes (i.e., the cybotactic region) when they are dissolved in a 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) room-temperature ionic liquid as a function of temperature and added CO2 (T = 308 K; P = 0−150 bar). In dry [bmim][PF6] at 293 K, the cybotactic region exhibits a dielectric constant and refractive index of 11.4 ± 1.0 and 1.523 ± 0.025, respectively. The activation energy that describes the [bmim][PF6] viscous flow is 38.4 ± 0.9 kJ mol-1. The activation energy for solute rotational reorientation in [bmim][PF6] is equivalent to the activation energy for [bmim][PF6] viscous flow, indicating that solute rotational dynamics are correlated entirely with the [bmim][PF6] dynamics. There is nanosecond dipolar relaxation surrounding a solute dissolved in dry [bmim][PF6] at 293 K. Even though CO2 is highly soluble in [bmim][PF6] (CO2 mole fraction = 0.6 at 313 K and 68 bar), addition of up to 150 bar CO2 to [bmim][PF... |
| Databáze: | OpenAIRE |
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