Title data
Lüdecke, Jens ; van Smaalen, Sander ; Spijkerman, Albert ; de Boer, Jan L. ; Wiegers, Gerrit A.:
Commensurately modulated structure of 4Hb-TaSe₂ determined by x-ray crystal-structure refinement.
In: Physical Review B.
Vol. 59
(1999)
Issue 9
.
- pp. 6063-6071.
ISSN 0163-1829
DOI: https://doi.org/10.1103/PhysRevB.59.6063
Abstract in another language
The (13√a×13√a×c) superstructure of 4Hb-TaSe₂ at room temperature has been determined by x-ray crystal-structure refinement using (3+2)-dimensional superspace. The resulting modulation has its largest amplitudes for a longitudinal displacement of the Ta atoms in the octahedrally coordinated (T) layers, thus leading to a superstructure of hexagram-shaped clusters containing thirteen Ta atoms each. The atoms in the corresponding planes of Se atoms show a transversal modulation, which can be interpreted as the relaxation of these layers to the modulation of the Ta layers. Forming a similar pattern, modulations were found of the atoms in the layers with Ta in trigonal prismatic coordination (H layers), with amplitudes of about 1/10 of the sizes of the modulations in the T layers. These results confirm the presence of a charge-density wave in the T layers, while the modulations of the H layer can be assigned to elastic coupling between the two types of layers. The observation of nonzero displacements of the atoms of the H layers provides an interpretation for recent observations by scanning tunneling microscope (STM): the superstructure features observed by STM on the H layers is a direct consequence of the atomic displacements in this layer.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | Yes |
Institutions of the University: | Faculties > Faculty of Mathematics, Physics und Computer Science > Group Material Sciences > Chair Crystallography Faculties > Faculty of Mathematics, Physics und Computer Science > Group Material Sciences > Chair Crystallography > Chair Crystallography - Univ.-Prof. Dr. Sander van Smaalen Faculties Faculties > Faculty of Mathematics, Physics und Computer Science Faculties > Faculty of Mathematics, Physics und Computer Science > Group Material Sciences |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science > 530 Physics |
Date Deposited: | 10 Jun 2016 07:40 |
Last Modified: | 26 Aug 2022 07:01 |
URI: | https://eref.uni-bayreuth.de/id/eprint/32636 |