Structural Phase Diagram of PerovskiteA0.7A′0.3MnO3(A= La, Pr;A′= Ca, Sr, Ba): A NewImmaAllotype

✍ Scribed by P.G. Radaelli; M. Marezio; H.Y. Hwang; S.-W. Cheong

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 277 KB
• Volume: 122
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1996.0140

✦ Synopsis

with space group Pnma and R3c, were already known, The structural phase diagram of A 1؊x A x MnO 3 (A ‫؍‬ La, Pr, while the third, with space group Imma, is a new structural Y, . . .; A ‫؍‬ Ca, Sr, Ba, . . .) as a function of the average allotype of A 1Ϫx AЈ x MnO 3 . This new phase is present for A-site ionic radius ͗r A ͘ was determined from neutron powder large values of ͗r A ͘ at low temperature, and transforms diffraction data. In addition to the well-known Pnma and R3c into the well-known R3c phase with increasing temperaphases, a new orthorhombic phase, with space group Imma, ture through a first-order transition.