Single crystals of SrLaAlO₄ doped by Mn ions were obtained by the Czochralski method. The crystals were grown from the nonstoichiometric melts of SrLa_1,03Al_0,97O₄. This composition was reported earlier for obtaining of good quality SLA single crystal [1]. Thermal isolation of the system contains a ceramic disc between the crucible and the passive afterheater to ensure proper temperature gradient across the surface of the melt. Crystals were grown from iridium crucible of 50 mm in diameter. Crystal growth was conducted in pure nitrogen.

Manganese dopant was introduced into the melt in the form of MnO₂ oxide and was added to the above mentioned SLA compound. The assumed concentration of dopants in the melt was equal to 0, 02 and 0, 1 wt%. The pulling rate in the case of lower doping level was 1 mm/h and rotation rate was equal to 17 rpm. Good quality single crystals of 18 mm in diameter and 35 mm in length were grown using <100> seed orientated. Single crystals doped with 0.1 wt% of Mn were easily cracked, even when the pulling rate was reduced up to 0.7 mm/h. However, an inside some parts of crystal were good quality not cracked and were used in further investigations.

SLA doped with Mn²⁺ ions (0,02 mol%) was synthesized by modified sol-gel (Pechini) method as follows: lanthanum oxide was dissolved in solution of acetic acid, then strontium carbonate, aluminum nitrate, solution of nitric acid and manganese acetate were added. After two hours of stirring the ethylene glycol as polymerizing agent was used. Subsequently the solvent was evaporated and the xerogel was dried at 150°C for 12 hours, grinded in an agate mortar to obtain fine powder, next annealed at 1450ºC in furnace for 4 hours. The diffraction patern shows the one phase compound of SLA structure.

The purpose of the present work was to study electronic structure and magnetic properties of manganese ions in SrLaAlO₄ host.

Magnetic susceptibility was measured using a Quantum Design MPMS–XL–7AC SQUID magnetometer in the temperature range 1.9 – 400 K.

The XPS spectra were obtained using a PHI 5700/660 Physical Electronics Photoelectron Spectrometer with monochromatized Al K_α X–ray radiation (1486.6 eV).

The microstructural observations of the nanopowders as well as the microcompositional analysis were conducted on a JEOL–7600F scanning electron microscopy equipped with the Oxford X–ray energy dispersive spectroscope EDS.

                     Table 1. Magnetic measurements results.

Electronic structure measurements showed a decomposition of the surface of the nanocrystals SLA. Magnetic measurements confirmed the presence of Mn⁴⁺ in the measured doped samples what is essential for spectroscopic properties of such crystals.

Acknowledgements

This work was partially financed by the Polish National Science Centre under grant no. NN 515 500 440.

1. A. Pajaczkowska, A. Gloubokov, Synthesis, growth and characterization of tetragonal ABCO₄crystals, Prog. Crystal Growth and Charact. 36 (1998) 123–162.

2. W. Ryba-Romanowski, S. Gołąb, A. Gloubokov, A. Pajączkowska, Spectroscopic properties of chromium-doped SrLaAlO₄ single crystals, Opt. Mater. 4 (1995) 515–519.

3. W. Ryba-Romanowski, S. Gołąb, I. Sokólska, W.A. Pisarski, G. Dominiak-Dzik, A. Pajączkowska, M. Berkowski, Anisotropy of optical properties of SrLaAlO₄ and SrLaAlO₄:Nd, J. Alloys Comp. 217 (1995) 263–267.

4. L. Vasylechko, N. Kodama, A. Matkovskii, Ya. Zhydachevskii, Crystal structure and optical spectroscopy of CaGdAlO₄:Er single crystal, J. Alloys Comp.300-301 (2000) 475–478.

5. Ya. Zhydachevskii, A. Suchocki, D. Sugak, A. Luchechko, M. Berkowski, S. Warchol, R. Jakiela, Optical observation of the recharging processes of manganese ions in YAlO3:Mn crystals under radiation and thermal treatments. J. Phys.: Condens. Matter 18 (2006) 5389–5403.

6. Ya. Zhydachevskii A. Suchocki, M. Berkowski, D. Sugak, A. Luchechko, S. Warchol, Technological approaches for improving thermoluminescent properties of the Czochralski-grownYAlO₃:Mn crystals. J.Cryst.Growth 310(2008) 3219–3232.

• 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: https://science24.com/paper/28945 must be provided.

1. Jan Czochralski and historical development of the Czochralski method - part 2
2. Influence of annealing process on SrLaAlO₄: Mn nanocrystals obtained by sol-gel method
3. Jan Czochralski and historical development of the Czochralski method - part 1
4. Comparison of magnetic properties of the monocrystalline and microcrystalline Gd₇Pd₃ compound
5. Comparison of magnetic properties of the monocrystalline and microcrystalline Gd₇Pd₃ compound
6. The highly versatile handle for synthesis of secondary amine derivatives with potential CNS activity: The Pipecolic Linker
7. Design, synthesis and anticonvulsant activity of new N-Mannich bases derived from 3-phenylpyrrolidine-  2,5-diones
8. The multiobjective based design, synthesis and evaluation of the arylsulfonamide/amide derivatives of arylxyethyl- and arylthioethyl- piperidines and pyrrolidines as a novel class of potent 5-HT₇ receptor antagonists
9. A novel handle for chemistry on solid support: the Pipecolic linker
10. Quinolinesulfonamides as potential 5-HT₇ and 5-HT_1A receptor ligands
11. Influence of hydrogen on hydrogenated cadmium telluride optical spectra
12. Solid-phase synthesis and preliminary biological investigation of arylpiperazine library as 5-HT_1A and 5-HT_2A receptor ligands
13. Synthesis by sol-gel method of nanocrystalline compounds within Y₂O₃(Nd₂O₃)–Al₂O₃ system for optical applications
14. XPS characterization of YAlO₃:Co single crystals
15. Magnetic properties of CeNi₄Mn single crystal
16. Growth and characterization of Nd, Yb – Yttrium oxide nanopowders obtained by sol-gel method
17. Luminescence characteristics of undoped and Eu-doped GdCOB single crystals and nanopowders
18. X-ray topography of GdCa₄O(BO₃)₃ doped of 4% Nd single crystal grown by Czochralski method
19. X-ray topography of Ca_0.5Sr_0.5NdAlO₄ single crystal
20. On the solubility of Nd³⁺ in Y₃Al₅O₁₂
21. Influence of hydrogen on optical spectra of hydrogenated CdTe
22. Crystal and electronic structure of GdPdX (X=Al, Si, Ga, Sn, Ge, In)
23. Magnetic properties of the GdTiSb and GdTiSn - the new intermetallic compounds.
24. SPECTROSCOPIC CHARACTERIZATION OF POLYACID MODIFIED RESIN COMPOSITES (PMRC)
25. Characterisation of newly obtained Pb(Mn1/3Nb2/3)O3 ceramics by XRD, XPS and dielectric permittivity tests.
26. Electronic structure of AgNbO₃ single crystals
27. XPS investigations of NdGaO3 wafers
28. Conventional and SR reflection topography of GdCa₄O(BO₃)₃ crystals