Potassium self-diffusion in a K-rich single-crystal alkali feldspar

Author(s)
Fabian Hergemoeller, Matthias Wegner, Manfred Deicher, Herbert Wolf, Florian Brenner, Herbert Hutter, Rainer Abart, Nicolaas A. Stolwijk
Abstract

The paper reports potassium diffusion measurements performed on gem-quality single-crystal alkali feldspar in the temperature range from 1169 to 1021 K. Natural sanidine from Volkesfeld, Germany was implanted with

43K at the ISOLDE/CERN radioactive ion-beam facility normal to the (001) crystallographic plane. Diffusion coefficients are well described by the Arrhenius equation with an activation energy of 2.4 eV and a pre-exponential factor of 5×10-6m2/s, which is more than three orders of magnitude lower than the

22Na diffusivity in the same feldspar and the same crystallographic direction. State-of-the-art considerations including ionic conductivity data on the same crystal and Monte Carlo simulations of diffusion in random binary alloy structures point to a correlated motion of K and Na through the interstitialcy mechanism.

Organisation(s)
Department of Lithospheric Research
External organisation(s)
Universität Münster, Universität des Saarlandes, Technische Universität Wien
Journal
Physics and Chemistry of Minerals
Volume
44
Pages
345-351
No. of pages
7
ISSN
0342-1791
DOI
https://doi.org/10.1007/s00269-016-0862-1
Publication date
05-2017
Peer reviewed
Yes
Austrian Fields of Science 2012
105120 Petrology
Keywords
ASJC Scopus subject areas
Geochemistry and Petrology, General Materials Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/d521032e-500b-4c2c-b9fb-1ceb62900698