Lithium cobalt(II) pyrophosphate, Li1.86CoP2O7, from synchrotron X-ray powder data

• Main Authors: M. Stanley Whittingham, Natasha A. Chernova, Shailesh Upreti, Hui Zhou
• Format: Article
• Language: English
• Published: International Union of Crystallography 2011-10-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536811038451

Structure refinement of high-resolution X-ray powder diffraction data of the title compound gave the composition Li1.865CoP2O7, which is also verified by the ICP measurement. Two Co sites exist in the structure: one is a CoO5 square pyramid and the other is a CoO6 octahedron. They share edges and are further interconnected through P2O7 groups, forming a three-dimensional framework, which exhibits different kinds of intersecting tunnels containing Li cations and could be of great interest in Li ion battery chemistry. The structure also exhibits cation disorder with 13.5% Co residing at the lithium (Li1) site. Co seems to have an average oxidation state of 2.135, as obtained from the strutural stochiometry that closely supports the magnetic susceptibility findings.