Single-Crystal X-Ray Diffraction Studies of Homologues in the Series nBa(Nb,Zr)O3+3mNbO with n=2, 3, 4, 5 and m=1

✍ Scribed by G. Nilsson; G. Svensson

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 498 KB
• Volume: 156
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8965

✦ Synopsis

were found in the reduced Ba+Nb+Zr+O system. Single-crystal X-ray di4raction data were collected for all the crystals. For all homologues the space group was found to be P4/mmm. The structures can be described as intergrowths of Ba(Nb, Zr)O 3 perovskite and NbO slabs. The re5ned cell parameters and compositions of the 2:1, 3:1, and 4:1 homologues are a ‫؍‬ 4.1768(5) A s and c ‫؍‬ 12.269(2) A s for Ba 2 Nb 4.5(1) Zr 0.5(1) O 9 , a ‫؍‬ 4.1769(5) A s and c ‫؍‬ 16.493(3) A s for Ba 3؉ Nb 4.8(2)؊ Zr 1.2(2) O 12؊ ( ‫؍‬ 0.098( 4)), and a ‫؍‬ 4.1747(6) A s and c ‫؍‬ 20.619(4) A s for Ba 4؉ Nb 5.1(4)؊ Zr 1.9(4) O 15؊ ( ‫؍‬ 0.270( 9)). The re5ned cell parameters of the 5:1 homologue are a ‫؍‬ 4.1727(3) A s and c ‫؍‬ 24.804(3) A s . Zr replaces Nb only in the NbO 6 octahedra found in the perovskite slabs.