7Li-NMR determination of stability constants as a function of temperature for lithium-crown ether complexes in a molten salt mixtures

Zahl A, van Eldik R (1994)


Publication Type: Journal article, Original article

Publication year: 1994

Journal

Original Authors: Gerhard A., Cobranchi D., Garland B., Highley A., Huang Y., Kenya G., Zahl A., van Eldik R., Petrucci S., Eyring E.

Publisher: American Chemical Society

Book Volume: 98

Pages Range: 7923-7928

Journal Issue: 32

URI: https://www.scopus.com/record/display.uri?eid=2-s2.0-0028493342&origin=inward

Abstract

The stability constants of several crown ethers with lithium ion were determined by Li-NMR measurements. A room temperature, basic molten salt of the compostion of 55/45 mol % 1-methyl-3-ethyl-imidazolium chloride to aluminum (III) chloride was used as solvent. On the basis of a 1:1 complex formation the following order was found for the stability constants of the investigated crown ethers: 18-crown-6 < 12-crown-4 < benzo-15-crown-5 < 15-crown-5. A temperature dependence study for 12-crown-4, benzo-15-crown-5, and 15-crown-5 was undertaken for the range 5-84°C. Values of ΔH and ΔS were calculated. At 5.5°C the splitting of the single, fast exchange peak into two separate signals was observed for benzo-15-crown-5, providing further evidence for the formation of the 1:1 complex.

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How to cite

APA:

Zahl, A., & van Eldik, R. (1994). 7Li-NMR determination of stability constants as a function of temperature for lithium-crown ether complexes in a molten salt mixtures. Journal of Physical Chemistry, 98(32), 7923-7928.

MLA:

Zahl, Achim, and Rudi van Eldik. "7Li-NMR determination of stability constants as a function of temperature for lithium-crown ether complexes in a molten salt mixtures." Journal of Physical Chemistry 98.32 (1994): 7923-7928.

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