Structural Properties of Li_xMn₂O₄ as Investigated by Molecular Dynamics and Density Functional Theory

Abstract

We performed density functional calculations and molecular dynamics (MD) simulations to study the structural properties of LiMn 2 O 4 . The periodic density functional calculations revealed that LiMn 2 O 4 had a locally distorted structure due to the different local structures around Mn 3+ and Mn 4+ . The trajectory plots of Mn 3+ in Li 0.4 Mn 2 O 4 at 300 K obtained by MD simulations indicated that Mn 3+ ions moved easily from the 16d site, which is the original position of Mn 3+ ion in the spinel structure. It was observed that the Mn 3+ ions moved with greater ease at low lithium concentrations, resulting in unstable Li x Mn 2 O 4 structures.