Dynamics of solvation in supercooled liquids confined to the pores of sol-gel glasses

C. Streck, Yu B. Mel'nichenko, Ranko Richert

Research output: Contribution to journalArticle

98 Citations (Scopus)

Abstract

We have measured the solvation dynamics of the probe molecule quinoxaline in a glass-forming solvent, 2-methyltetrahydrofuran, geometrically confined to the pores of sol-gel glasses having nominal pore diameters ø=2.5, 5.0, and 7.5 nm. Within the time range l ms≤t≤l s the a process and a second extremely slow process are observed, On the basis of emission spectra, the latter relaxation is assigned to a surface layer with strongly frustrated dynamics, opposed to the picture of a certain fraction of pores entirely filled with liquid of reduced molecular mobility. According to the Stokes-shift results for porous samples, the thickness of this surface layer increases significantly with Tg←T for the system under study. The results are compared with solvation dynamic experiments for the bulk solvent and with dielectric relaxation measurements.

Original languageEnglish (US)
Pages (from-to)5341-5347
Number of pages7
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume53
Issue number9
StatePublished - Mar 1 1996
Externally publishedYes

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Solvation
Sol-gels
solvation
gels
porosity
Glass
glass
surface layers
Liquids
liquids
quinoxalines
Quinoxalines
Dielectric relaxation
emission spectra
Molecules
probes
shift
molecules
Experiments

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Dynamics of solvation in supercooled liquids confined to the pores of sol-gel glasses. / Streck, C.; Mel'nichenko, Yu B.; Richert, Ranko.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 53, No. 9, 01.03.1996, p. 5341-5347.

Research output: Contribution to journalArticle

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