Anomalous Conductivity in the Rutile Structure Driven by Local Disorder
Document Type
Article
Publication Date
8-22-2019
Publication Title
Journal of Physical Chemistry Letters
Volume
10
Issue
18
First page number:
5351
Last page number:
5356
Abstract
Many rutile-type materials are characterized by a softness in shear with pressure which is coupled to a Raman-active librational motion. Combining direct studies of anion positions in SnO2 with measurements of its electronic properties, we find a correlation between O sublattice disorder between 5 and 10 GPa and an anomalous decrease up to 4 orders of magnitude in electrical resistance. Hypotheses into the atomistic nature of the phenomenon are evaluated via ab initio calculations guided by extended X-ray absorption fine structure spectroscopy analysis, and the most likely mechanism is found to be the displacement of single anions resulting from the pressure-induced softening of the librational mode. On the basis of this mechanism, we propose that the same behavior should feature across all materials exhibiting a rutile → CaCl2 phase transition and that conductivity in other rutile-type materials could be facilitated at ambient pressure by appropriate design of devices to enhance defects of this nature.
Disciplines
Chemistry | Physics
Language
English
Repository Citation
Smith, D.,
Sneed, D.,
Dasenbrock-Gammon, N.,
Snider, E.,
Smith, G. A.,
Childs, C.,
Pigot, J. S.,
Velisavljevic, N.,
Park, C.,
Lawler, K. V.,
Dias, R. P.,
Salamat, A.
(2019).
Anomalous Conductivity in the Rutile Structure Driven by Local Disorder.
Journal of Physical Chemistry Letters, 10(18),
5351-5356.
http://dx.doi.org/10.1021/acs.jpclett.9b01633