pith. sign in

arxiv: cond-mat/0508444 · v1 · submitted 2005-08-19 · ❄️ cond-mat.str-el

Structural properties and cation ordering in layered hexagonal CaxCoO2

H.X. Yang , Y.G. Shi , X. Liu , R.J. Xiao , H.F. Tian , J.Q. Li This is my paper
classification ❄️ cond-mat.str-el
keywords structuralcationmaterialsaroundcaxcoo2distortionnaxcoo2ordered
0
0 comments X
read the original abstract

A series of CaxCoO2 (0.15 <= x <= 0.40) materials have been prepared by means of ion exchange reaction from NaxCoO2. Transmission electron microscopy (TEM) measurements revealed a rich variety of structural phenomena resulting from cation ordering, structural distortion and twinning. Systematical structural analysis, in combination with the experimental data of NaxCoO2 (0.15 <= x <= 0.8) and SrxCoO2 (1.5 <= x <= 0.4) systems, suggests that there are two common well-defined cation ordered states corresponding respectively to the orthorhombic superstructure at around x = 1/2 and the 31/2a&#61620;31/2a superstructure at around x = 1/3 in this kind of system. Multiple ordered states, phase separation, and incommensurate structural modulations commonly appear in the materials with 0.33 < x < 0.5. The TEM observations also reveals an additional periodic structural distortion with q2 = a* / 2 in materials for x <= 0.35. This structural modulation also appears in the remarkable superconducting phase Na0.33CoO2 1.3H2O.

This paper has not been read by Pith yet.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.