Synthesis and Structure of New Perovskite Phase in the La–Ti–Al–O System

✍ Scribed by P.R. Slater; J.T.S. Irvine

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 94 KB
• Volume: 146
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1999.8388

✦ Synopsis

In this paper we report the synthesis of a new phase in the La+Ti+Al+O system. A starting composition La 2 TiAlO 6.5 and synthesis conditions of 14003C under H 2 /Ar (5%/95%) resulted in a perovskite with a monoclinic (I 2/a; a ‫؍‬ 7.686, b ‫؍‬ 5.435, c ‫؍‬ 5.424 A s , ‫؍‬ 90.203) cell. Although it was necessary to synthesize this material under reducing conditions, once prepared it was stable to subsequent oxidation at high temperatures in air. Structure re5nement using neutron di4raction suggests the possible incorporation of a small amount of La on the small cation sites along with a La de5ciency on the large cation sites, such that the composition may be written as La 0.83 (La 0.07 Al 0.465 Ti 0.465 )O 2.9 .