Synthesis and Structural Characterization of Lithium Iron Diarsenate, LiFeAs2O7

✍ Scribed by Sue-Lein Wang; Chih-hsien Wu; Sheng-Nan Liu

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 221 KB
• Volume: 113
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1338

✦ Synopsis

A new iron(III) diarsenate, (\mathrm{LiFeAs}{2} \mathrm{O}{7}), was synthesized hydrothermally at (230^{\circ} \mathrm{C}) and characterized by single-crystal (\mathrm{X})-ray diffraction. The compound crystallizes in the monoclinic space group (C 2) (No. 5) with (a=6.676(2) \AA, b=8.285(2) \AA, c=4.744(2) \AA), (\beta=103.96(2)^{\circ}, Z=2), and (R=0.0192). SHG measurements on a powder sample confirm the absence of center of symmetry in the structure. The structure consists of intersecting tunnels running along the [001] and (\langle 110\rangle) directions, and the (\mathrm{Li}^{+})ions are located at the intersection of these tunnels. The framework is built up from corner-sharing (\mathrm{FeO}{6}) octahedra and (\mathrm{As}{2} \mathrm{O}{7}) groups. The structure is discussed along with the phosphate analog (\mathrm{LiFeP}{2} \mathrm{O}_{7}). (1994 Academic Press, Inc.