Publications

Mechanical Properties of Intermetallic Clathrates

Author(s)

Matthias Falmbigl, Stephan Puchegger, Peter Franz Rogl

Abstract

The present work provides a comprehensive compilation and discussion

covering hardness, experimentally determined elastic properties, thermal expan-

sion, and Debye and Einstein temperatures for intermetallic clathrates. Comparing

hardness values and elastic properties a major influence of the framework atoms is

observed. Hardness and elastic moduli change linearly with the Si/Ge-ratio. Also a

linear temperature dependence of the elastic properties is observed. In the case that

vacancies are present in the clathrate framework, the hardness of different com-

pounds decreases almost linearly with an increasing vacancy-content. As Debye

and Einstein temperatures are of significance for the vibrational spectra and per-

formance of thermoelectric materials, corresponding values extracted from various

measurement techniques such as thermal expansion, sound velocity, specific heat,

electrical resistivity or X-ray absorption and diffraction measurements are evalu-

ated. The Debye temperatures correlate with the melting temperatures of the

intermetallic clathrates, and the Einstein temperatures for similar guest atoms

show a linear dependence on the cage size. Wherever available, experimental data

are compared with those from DFT model simulations. In general the experi-

mentally derived values match those theoretically calculated

Organisation(s)

Department of Physical Chemistry, Faculty Center for Nano Structure Research

Volume

199

Pages

277-326

No. of pages

DOI

https://doi.org/10.1007/978-94-017-9127-4_10

Publication date

08-2014

Austrian Fields of Science 2012

104017 Physical chemistry, 104011 Materials chemistry

ASJC Scopus subject areas

General Materials Science

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