Low-temperature features in the heat capacity of unary metals and intermetallics for the example of bulk aluminum and Al3{S}c
A. Gupta, B. Tas Kavakbasi, B. Dutta, B. Grabowski, M. Peterlechner, T. Hickel, S. V. Divinski, G. Wilde, J. Neugebauer,
Volume: 95. Pages: 094307
DOI: 10.1103/PhysRevB.95.094307
Published: 2017
Abstract
We explore the competition and coupling of vibrational and electronic
contributions to the heat capacity of Al and Al3Sc at temperatures
below 50 K, combining experimental calorimetry with highly converged
finite-temperature density functional theory calculations. We find
that semilocal exchange-correlation functionals accurately describe
the rich feature set observed for these temperatures, including electron-phonon
coupling. Using different representations of the heat capacity, we
are therefore able to identify and explain deviations from the Debye
behavior in the low-temperature limit and in the temperature regime
30–50 K as well as the reduction of these features due to the addition
of Sc.