Common Features of Gallium Perovskites

• Published in: Crystal research and technology (1979) Vol. 36; no. 8-10; pp. 789 - 800
• Main Authors: Aleksiyko, R., Berkowski, M., Byszewski, P., Dabrowski, B., Diduszko, R., Fink-Finowicki, J., Vasylechko, L. O.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Berlin WILEY-VCH Verlag Berlin GmbH 01-10-2001; WILEY‐VCH Verlag Berlin GmbH; Wiley-VCH
• Subjects: Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; crystal growth; Czochralski; Exact sciences and technology; floating zone; Growth from melts; zone melting and refining; Inorganic compounds; Materials science; Methods of crystal growth; physics of crystal growth; neutron diffraction; perovskite related structures; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Water, oxides, hydroxides, peroxides; X-ray diffraction; Oxides Mixed; Samarium oxides; Temperature dependence; Lanthanum oxides; Inorganic compounds; Neutron diffraction; Neodymium oxides; Czochralski method; Perovskites; XRD; Ionic radius; Floating zone; Rare earth compounds; Experimental study; Strontium oxides; Gallium oxides; Monocrystals; Powder pattern; Solid solutions; Synchrotron radiation; Crystal growth from melts; Crystal structure
• ISSN: 0232-1300; 1521-4079
• DOI: 10.1002/1521-4079(200110)36:8/10<789::AID-CRAT789>3.0.CO;2-K

The Czochralski and floating zone methods have been used to grow single crystals of gallium perovskites solid solutions with rare earth elements La, Pr, Nd, Sm and with Sr. The structure of the crystals has been investigated by powder X‐ray, synchrotron radiation and neutron diffraction methods over a wide temperature range. The unit cell volume at room temperature varies from approximately 228 to 236 Å3 in Sm0.75Nd0.25GaO3 and La0.88Sr0.12GaO3‐δ, respectively. Position of atoms in the unit cell and evolution of perovskite lattice deformation induced by continuously varying average rare earth ionic radius is discussed. The unit cell parameters including atoms positions, thermal expansion coefficients, segregation coefficients and phase transition temperature scale with the unit cell volume in all investigated crystals. All these parameters may be represented as a function of average ionic radius of rare elements, however, this value is not well determined in these compounds because of ill determined coordination number.