Stress-induced charge-ordering process in LiMn2O4

In this letter we report the stress-induced Mn charge-ordering process in the LiMn2O4 spinel, evidenced by the lattice strain evolutions due to the Jahn-Teller effects. In situ neutron diffraction reveals the initial stage of this process at low stress, indicating the eg electron localization at the preferential Mn sites during the early phase transition as an underlying charge-ordering mechanism in the charge-frustrated LiMn2O4. The initial stage of this transition exhibits as a progressive lattice and charge evolution, without showing a first-order behavior.