Structural Origin of the Mixed Glass Former Effect in Sodium Borophosphate Glasses Investigated with Neutron Diffraction and Reverse Monte Carlo Modeling
Journal article, 2015

The mixed glass former systems 0.35Na(2)O + 0.65[xB(2)O(3) + (1 - x)P2O5] and 0.5Na(2)O + 0.5[xB(2)O(3) + (1 - x)P2O5] with x = 0-1 were investigated with neutron diffraction (ND) together with reverse Monte Carlo (RMC) modeling of 0.35Na(2)O + 0.65[xB(2)O(3) + (1 - x)P2O5]. The results show that the structure of both systems is reflected by an intermediate-range ordering, with a characteristic x-dependent length scale of about 4-6 angstrom and which contracts slightly with the increase of the Na concentration. Results obtained from RMC modeling of the 0.35Na(2)O + 0.65[xB(2)O(3) + (1 - x)P2O5] system, using both previously reported X-ray diffraction (XRD) data as well as the here obtained ND data as independent constraints in the modeling, show that the intermediate-range structural features, notably the Na coordination and volume fraction of the conducting pathways, are only weakly dependent on the choice of the constraints used. In particular, we observe that the volume fraction of the conducting pathways and the activation energy for ionic conduction are only weakly correlated to each other, as opposed to what is found for binary alkali borate and phosphate glasses.

Author

Maths Karlsson

Chalmers, Applied Physics, Condensed Matter Physics

M. Schuch

Universitat Osnabruck

R. Christensen

Iowa State University

P. Maass

Universitat Osnabruck

Steve Martin

Iowa State University

S. Imberti

ISIS Facility

Aleksandar Matic

Chalmers, Applied Physics, Condensed Matter Physics

Journal of Physical Chemistry C

1932-7447 (ISSN) 1932-7455 (eISSN)

Vol. 119 49 27275-27284

Subject Categories

Physical Chemistry

DOI

10.1021/acs.jpcc.5b09176

More information

Created

10/7/2017