aalto1 untyped-item.component.html
Ab initio computational study on the lattice thermal conductivity of Zintl clathrates [Si19 P4]Cl4 and Na4[Al4Si19]
Loading...
Access rights
openAccess
publishedVersion
URL
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Unless otherwise stated, all rights belong to the author. You may download, display and print this publication for Your own personal use. Commercial use is prohibited.
Date
Department
Major/Subject
Mcode
Degree programme
Language
en
Pages
Series
Physical Review B, Volume 94, issue 5
Abstract
The lattice thermal conductivity of silicon clathrate framework Si23 and two Zintl clathrates, [Si19P4]Cl4 and Na4[Al4Si19], is investigated by using an iterative solution of the linearized Boltzmann transport equation in conjunction with ab initio lattice dynamical techniques. At 300 K, the lattice thermal conductivities for Si23, [Si19P4]Cl4, and Na4[Al4Si19] were found to be 43 W/(m K), 25 W/(m K), and 2 W/(m K), respectively. In the case of Na4[Al4Si19], the order-of-magnitude reduction in the lattice thermal conductivity was found to be mostly due to relaxation times and group velocities differing from Si23 and [Si19P4]Cl4. The difference in the relaxation times and group velocities arises primarily due to the phonon spectrum at low frequencies, resulting eventually from the differences in the second-order interatomic force constants (IFCs). The obtained third-order IFCs were rather similar for all materials considered here. The present findings are similar to those obtained earlier for some skutterudites. The predicted lattice thermal conductivity of Na4[Al4Si19] is in line with the experimentally measured thermal conductivity of recently synthesized type-I Zintl clathrate Na8[Al8Si38] (polycrystalline samples).
Description
Keywords
Other note
Citation
Härkönen, V J & Karttunen, A J 2016, 'Ab initio computational study on the lattice thermal conductivity of Zintl clathrates [Si19 P4]Cl4 and Na4[Al4Si19]', Physical Review B, vol. 94, no. 5, 054310. https://doi.org/10.1103/PhysRevB.94.054310