Diffusion kinetics and correlation effects for self-diffusion via vacancy pairs and triple defects in the sphalerite structure

1H and 19F spin-lattice relaxation experiments have been performed for butyltriethylammonium bis(trifluoromethanesulfonyl)imide in the temperature range from 258 to 298 K and the frequency range from 10 kHz to 10 MHz. The results have thoroughly been analysed in terms of a relaxation model taking into account relaxation pathways associated with 1H–1H, 19F–19F and 1H–19F dipole–dipole interactions, rendering relative translational diffusion coefficients for the pairs of ions: cation–cation, anion–anion and cation–anion, as well as the rotational correlation time of the cation. The relevance of the 1H–19F relaxation contribution to the 1H and 19F relaxation has been demonstrated. A comparison of the diffusion coefficients has revealed correlation effects in the relative cation–anion translational movement. It has also turned out that the translational movement of the anions is faster than of cations, especially at high temperatures. Moreover, the relative cation–cation diffusion coefficients have been compared with self-diffusion coefficients obtained by means of NMR (Nuclear Magnetic Resonance) gradient diffusometry. The comparison indicates correlation effects in the relative cation–cation translational dynamics—the effects become more pronounced with decreasing temperature.

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CALCULATION OF CORRELATION EFFECTS FOR GRAIN-BOUNDARY AND DISLOCATION-PIPE SELF-DIFFUSION.

10.2172/4637986 ◽

1972 ◽

Author(s):

J.T. Robinson ◽

N.L. Peterson

Keyword(s):

Grain Boundary ◽

Correlation Effects ◽

Self Diffusion ◽

Dislocation Pipe

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Probing Diffusion Kinetics with Secondary Ion Mass Spectrometry

MRS Bulletin ◽

10.1557/mrs2009.212 ◽

2009 ◽

Vol 34 (12) ◽

pp. 907-914 ◽

Cited By ~ 63

Author(s):

Roger A. De Souza ◽

Manfred Martin

Keyword(s):

Mass Spectrometry ◽

Secondary Ion Mass Spectrometry ◽

Transport Processes ◽

Fast Diffusion ◽

Diffusion Kinetics ◽

Analytical Technique ◽

Self Diffusion ◽

Solid State Ionics ◽

Ion Mass Spectrometry ◽

Secondary Ion

AbstractSecondary ion mass spectrometry (SIMS) is a powerful analytical technique for determining elemental and isotopic distributions in solids. One of its main attractions to researchers in the field of solid-state ionics is its ability to distinguish between isotopes of the same chemical element as a function of position in a solid. With enriched stable isotopes as diffusion sources, this allows self-diffusion kinetics in solids to be studied. In this article, taking oxygen isotope diffusion in oxides as our main example, we present the standard experimental method, and, subsequently, we discuss several promising developments, in particular the opportunities offered by thin-film geometries, and the investigation of inhomogeneous systems, including possible fast diffusion along grain boundaries and making space-charge layers at interfaces “visible.” These examples demonstrate that SIMS is capable of probing mass transport processes over various length scales, ranging from some nanometers to hundreds of micrometers.

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