Crystal structure and physical properties of a misfit-layered cobaltite (CaOH)1.14CoO2

We have studied the crystal structure and transport properties of the new cobalt oxide (CaOH)(1.14)CoO2. The compound has the layer structure, which consists of CdI2-type CoO2 layers and rock-salt-type double CaOH atomic layers. The two subcells have incommensurate periodicity along the a-axis, resulting in a modulated crystal structure due to the inter-subcell interaction. The structural modulation affects carrier conduction through the potential randomness. We found that the two-dimensional (2-D) variable-range-hopping-type hole conduction is dominant at low temperature. (c) 2006 Elsevier B.V. All rights reserved.