X-ray absorption study of the electronic structure of Li-excess spinel Li1+xTi2-xO4 (0≤x≤0.33)

Li-excess spinel oxide, Li1+xTi2-xO4 (0less than or equal toxless than or equal to0.33), was investigated by x-ray absorption spectra (XAS) technique. XAS results revealed that both oxygen and titanium ions affect electronic structural changes in the system. Early transition metal compounds are considered to have smaller d-d Coulomb correlation energy (U-dd) than p-d Charge-transfer energy (Delta), indicating that electronic transfer for charge compensation occurs mainly on transition metal. However, present XAS results show that considerable charge-transfer character due to strong hybridization between titanium 3d and oxygen 2p orbitals exists in this early transition metal oxide system. (C) 2004 American Institute of Physics.