1 research outputs found
Influence of Structural Disorder on Hollandites A<sub><i>x</i></sub>Ru<sub>4</sub>O<sub>8</sub> (A<sup>+</sup> = K, Rb, Rb<sub>1โ<i>x</i></sub>Na<sub><i>x</i></sub>)
Structural
disorder can play an important role in the electrical properties of
correlated materials. In this work we examine the average and local
disorder in hollandites A<sub><i>x</i></sub>Ru<sub>4</sub>O<sub>8</sub> (A<sup>+</sup> = K, Rb, Rb<sub>1โ<i>x</i></sub>Na<sub><i>x</i></sub>) through neutron total scattering
techniques. Samples with A<sup>+</sup> = Rb, Rb<sub>1โ<i>x</i></sub>Na<sub><i>x</i></sub> exhibit the largest
amount of local disorder as evidenced by higher atomic displacement
parameters, and as a result, a weakened temperature dependence of
the resistivity is observed upon cooling as compared to K<sub><i>x</i></sub>Ru<sub>4</sub>O<sub>8</sub>. All samples exhibit
anisotropic resistivity that is dominated by metallic conductivity
at lower temperatures, and this is corroborated by Pauli paramagnetic
behavior throughout the measured temperature regime