Title data
Lüdecke, Jens ; Schneider, Martin ; van Smaalen, Sander:
Independent q→ and 2q→ Distortions in the Incommensurately Modulated Low-Temperature Structure of NiTa₂Se₇.
In: Journal of Solid State Chemistry.
Vol. 153
(2000)
Issue 1
.
- pp. 152-157.
ISSN 0022-4596
DOI: https://doi.org/10.1006/jssc.2000.8766
Abstract in another language
The modulated low-temperature structure of NiTa1.98Nb0.02Se7 has been determined by X-ray diffraction using synchrotron radiation. The superspace group of the modulated structure at 15 K is C2/m (0, qb, 0) s0 with qb=0.483(2). The lattice parameters were determined to a=13.807(6) Å, b=3.483(1) Å, c=18.564(11) Å, and β=108.95(4)° with Z=4. Satellite reflections up to second order were measured. Refinement with first- and second-order harmonic components of the modulation functions converged to R=0.059. The first-order harmonic was found predominantly on the double chain of Ni and Se2 atoms. Shifts were found parallel to the Full-size image (<1 K) and Full-size image (<1 K) axes, in good agreement with earlier investigations. The major part of the second harmonic was found on the Ta2 atoms, with amplitudes of secondary importance on the surrounding Se atoms. Shifts of the Ta2 atoms were found parallel to Full-size image (<1 K), thus forming a longitudinal wave. It is argued that the modulations according to the first-order and the second-order harmonics should be considered as independent CDW's.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | Yes |
Keywords: | incommensurate structures; charge density waves; phase transitions |
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: | 23 Mar 2016 07:22 |
Last Modified: | 15 May 2024 11:55 |
URI: | https://eref.uni-bayreuth.de/id/eprint/32002 |