Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-09T08:22:28.070Z Has data issue: false hasContentIssue false

Direct and Indirect Effects of Filling on Electronic Structure of Skutterudites

Published online by Cambridge University Press:  31 January 2011

Daehyun Wee
Affiliation:
[email protected], Robert Bosch LLC, Research and Technology Center, 4009 Miranda Ave, Suite 200, Palo Alto, California, 94304, United States
Boris Kozinsky
Affiliation:
[email protected], Robert Bosch LLC, Research and Technology Center, Cambridge, Massachusetts, United States
Fornari Marco
Affiliation:
[email protected], Central Michigan University, Department of Physics, Mt. Pleasant, Michigan, United States
Nicola Marzari
Affiliation:
[email protected], Massachusetts Institute of Technlogy, Department of Materials Science and Engineering, Cambridge, Massachusetts, United States
Get access

Abstract

We perform ab-initio computations to investigate the family of CoSb3 skutterudites in an attempt to develop deeper understanding of the effect of fillers. Primary focus is on Ba-filled CoSb3 systems, while Ca and Sr-filled systems are also compared for checking consistency. We analyze both global and local structural effects of filling. We show the specific deformation of Sb network introduced by the filler. Such a deformation is localized around the filler site since soft Sb rings accommodate the distortion. Rearrangement of Sb atoms affects the band structures, and we perform additional analysis to clarify the effect of volume on the band gap. Phonon dispersions are briefly discussed, and filler-dominated vibrations are identified. These modes form the first optical modes at Γ. They manifest themselves in phonon dispersion curves as flat lines, showing that they are localized, while filler vibration is strongly coupled with nearby Sb atoms.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Baroni, S., Gironcoli, S. de, Corso, A. Dal, and Giannozzi, P.. Reviews of Modern Physics 73, 515–562 (2001).Google Scholar
2 Baroni, S., Corso, A. Dal, Gironcoli, S. de, Giannozzi, P., Cavazzoni, C., Ballabio, G., Scandolo, S., Chiarotti, G., Focher, P., Paswuarello, A., Laasonen, K., Trave, A., Car, R., Marzari, N., and Kokalj, A., Quantum-ESPRESSO. http://www.pwscf.org/Google Scholar
3 Madsen, G.K.H. and Singh, D.J., Computer Physics Communications 175, 67–71 (2006).Google Scholar
4 Takizawa, H., Miura, K., Ito, M., Suzuki, T., and Endo, T.. Journal of Alloys and Compounds 282, 79–83 (1999).Google Scholar
5 Wentzcovitch, R., VLAB. http://www.vlab.msi.umn.edu/Google Scholar
6 Schmidt, T., Kliche, G., and Lutz, H.D., Acta Crystallographica (Section C)-Crystal Structure Communications 43, 1678–1679 (1987).Google Scholar
7 Jung, D.W., Whangbo, M.H., and Alvarez, S., Inorganic Chemistry 29, 2252–2255 (1990).Google Scholar
8 Sofo, J.O. and Mahan, G.D., Physical Review B 58, 15620–15623 (1998).Google Scholar
9 Ghosez, Philippe and Veithen, Marek, Journal of Physics-Condensed Matter 19, 096002 (2007).Google Scholar
10 Kurmaev, E.Z., Moewes, A., Shein, I.R., Finkelstein, L.D., Ivanovskii, A.L., and Anno, H., Journal of Physics-Condensed Matter 16, 979–987 (2004).Google Scholar
11 Lefebvre-Devos, I., Lassalle, M., Wallart, X., Olivier-Fourcade, J., Monconduit, L.R., and Jumas, J.C., Physical Review B 63, 125110 (2001).Google Scholar
12 Martin, R. M., Electronic Structure: Basic Theory and Practical Methods, Cambridge University Press (2004).Google Scholar
13 Caillat, T., Borshchevsky, A., and Fleurial, J.P., Journal of Applied Physics 80, 4442–4449 (1996).Google Scholar
14 Yang, J., Zhang, W., Bai, S.Q., Mei, Z., and Chen, L., Applied Physics Letters 90, 192111 (2007).Google Scholar