Work

Transport and thermodynamic properties under anharmonic motion in type-I Ba 8 Ga 16 Sn 30 clathrate

Year: 2012

Type: article

Abstract: Anharmonic guest atom oscillation has direct connection to the thermal transport and thermoelectric behavior of type-I Ba${}_{8}$Ga${}_{16}$Sn${}_{30}$ clathrates. This behavior can be observed through several physical properties, with for example the heat capacity providing a measure of the overall excitation level structure. Localized anharmonic excitations also influence the low-temperature resistivity, as we show in this paper. By combining heat capacity, transport measurements, and our previous NMR relaxation results, we address the distribution of local oscillators in this material, as well as the shape of the confining potential and the excitation energies for Ba(2) ions in the cages. We also compare to the soft-potential model and other models used for similar systems. The results show good agreement between the previously deduced anharmonic rattler potential and experimental data.

Source: Physical Review B

DOI: 10.1103/physrevb.85.214304

Authors: Xiang Zheng, Sergio Y. Rodriguez, Laziz Saribaev, Joseph H. Ross

Institution: Texas A&M University

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: bronze

Funders: National Science Foundation, Welch Foundation, Division of Materials Research

Awards: NIRT: Molecular Nanomagnets: Magnetic and Electronic Properties of Novel Magnetic Nanostructures and Nanostructured Materials, G8426295126, G86215084