Structure of a new type of satellite phase in YBa2Cu3O7−δ

✍ Scribed by A. Bertinotti; J. Hammann; D. Luzet; E. Vincent

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 700 KB
• Volume: 160
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(89)90054-3

✦ Synopsis

Superconducting single crystals of YBa2Cu~0,_,+ displaying a secondary phase pattern superimposed on the orthorhombic bulk phase pattern have been investigated by X-ray diffraction. The crystal structure of the satellite phase material has been solved and shown to correspond to a new alkaline earth oxocuprate (II) BaCu304. It has orthorhombic symmetry. The space group is Dit-Cmmm with a= 1O.986 A, b= 5.503 A, c= 3.923 8, and 2=2. All the oxygen atoms of the structure are involved in a 2-D network of copper-oxygen square planar coordination polyhedra having edge linkage. Short distances d( Cu-Cu) = 2.75* 8, are found along infinite 1 -D copper chains. Structural similarities with YBa2Cu,0,_d may explain the frequent occurrence of BaCu304 within the host phase, and consequently its possible role as a weak link between superconducting regions.