Low-temperature structural properties of orthorhombic TbAlO3, TmAlO3 and LuAlO3 perovskites

Dmytro M. Trots 1,2Leonid Vasylechko 3Anatoliy Senyshyn 2,3Tadeusz Łukasiewicz 4

1. Hamburger Synchrotronstrahlungslabor HASYLAB, Notkestrasse 85, Hamburg 22607, Germany
2. Technische Universität Darmstadt, Institute of Materials Science, Petersenstr. 23, Darmstadt 64287, Germany
3. Lviv Polytechnic National University, 12 Bandera, Lviv 79013, Ukraine
4. Institute of Electronic Materials Technology (ITME), Wólczyńska 133, Warszawa 01-919, Poland

Abstract
Perovskite type TbAlO3 and LuAlO3 rare-earth aluminates attract considerable interest as laser media [1,2]. This work is a continuation of our systematic studies on the crystal structure of perovskite type rare-earth aluminates and gallates. Here we report structural investigations on TbAlO3, TmAlO3 and LuAlO3 at low temperatures using high-resolution synchrotron powder diffraction performed at beamline B2 (HASYLAB/DESY). All three compounds possess the GdFeO3 type of structure (space group Pbnm) in the whole temperature range studied (20-300 K) and exhibit quite various thermal behaviours of the lattice parameters.
The thermal dependencies of the lattice parameters of LuAlO3 display a rather typical (nonlinear and smooth) increase with temperature, whereas the behaviour of TmAlO3 shows deviations from a “normal” law which are reflected in a “sigmoid” expansion of the lattice along the [100] direction. Unusual trends occur in the thermal behaviour of TbAlO3: at T~60 K all three unique elements of the thermal expansion tensor undergo the zero value which is indicated by the observed extrema on the thermal dependencies of the respective lattice parameters. The thermal expansion coefficient in the [100] direction of the perovskite cell α11 achieves one more negative minimum around 130 K and then increases through the zero value (ca. 200 K). The observed smooth and nonlinear increase of the lattice dimensions in LuAlO3 and the anomalous thermal behaviour occurred in TbAlO3 and TmAlO3 can be associated to interactions between phonons and the electron subsystem of rare-earth ions with open f-shell [3].


We are indebted to Andreas Berghaeuser for his help with maintenance of cryostat.
[1] Sardar et al., J APPL PHYS 100 (2006) 083108
[2] Drozdowski et al., NUCL INSTRUM METH A 562 (2006) 254
[3] Vasylechko et al., Handbook on the Physics and Chemistry of Rare-earths, ed. K. Gschneidner, J. Bunzli, and V. Pecharsky (Elsevier, Amsterdam), 39 (2008) in print

Legal notice
  • Legal notice:

    Copyright (c) Pielaszek Research, all rights reserved.
    The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
    In every case, proper references including Author(s) name(s) and URL of this webpage: http://science24.com/paper/15302 must be provided.

 

Related papers
  1. Czochralski growth and characterization of MgAl2O4 single crystals
  2. Precise lattice parameter measurements of the Sr0.72Ba0.25Nb2O5.97 single crystals
  3. Characterization of the defect structure in gadolinium orthovanadate single crystals grown by the Czochralski method
  4. Synchrotron topographic studies of domain structure in Czochralski grown PrxLa1-xAlO3 crystals
  5. Low-temperature expansion of metastable Pb1-xCdxTe solid solution
  6. Transparent Nd:YAG ceramics sintered from nanometric powders- effect of co-precipitation temperature on powder sinterability
  7. Structural instabilities in LnGaO3 perovskites at high pressures
  8. Effect of Zn doping on the tetragonally distorted CuFe2O4 structure
  9. Structures and properties of variously doped Mayenite investigated by neutron and synchrotron powder diffraction
  10. Structure-function relations of novel materials studied at neutron powder diffractometer SPODI
  11. Influence of Nd dopants to change of lattice parameters in YVO4 single crystals.
  12. Self-organized microstructure of TiO2-MnO
  13. Growth and microstructures of ZnO – WO3 and TiO2 – WO3 eutectic crystals
  14. The investigation of structural perfection and facetting in highly Er - doped Yb3Al5O12 crystals
  15. Self- organized eutectic microstructures for photonic crystals and metamaterials
  16. X-ray characterization of Sr0.61Ba0.39Nb2O6 single crystals
  17. Growth and investigation of optical properties of YAG:Co,Si single crystals.
  18. Growth and characterization of YAG single crystals doped with large concentration of vanadium.
  19. Ferroelectric and relaxor properties of strontium-barium niobate
  20. Preparation and sintering of nanometric oxides and YAG powders derived from nitrates by precipitation and co-precipitatin method
  21. Origin of the negative thermal expansion in perovskite-type PrGaO3
  22. Thermal expansion of NdGaO3 perovskite
  23. Crystal structure and thermal expansion of PrGaO3 in the temperature range 10-1253 K
  24. Twin structure of LSGMO crystals studied by Laue method

Presentation: Poster at 11th European Powder Diffraction Conference, Poster session, by Dmytro M. Trots
See On-line Journal of 11th European Powder Diffraction Conference

Submitted: 2008-04-28 18:18
Revised:   2009-06-07 00:48
Google
 
Web science24.com
© 1998-2022 pielaszek research, all rights reserved Powered by the Conference Engine