We studied the electronic and crystallographic structures of chemically deintercalated stoichiometric LiCo0.5Ni0.5O2. The experimental technique used in this study was X-ray absorption spectroscopy (both XANES and EXAFS). The results show that the electronic and crystallographic structures are similar to electrochemically deintercalated LiCo0.5Ni0.5O2. The electronic and structural similarity found here is in good agreement with previous XAS and X-ray diffraction (XRD) results. This means that the conclusions based on these studies could, in principle, be of use for electrochemically deintercalated LiCo0.5Ni0.5O2. (C) 2001 Elsevier Science B.V. All rights reserved.