Abstract:
We have performed an ab initio study of structural, electronic, magnetic, vibrational and thermal properties of the cubic spinel LiMn2O4 by employing the density functional theory, the linear-response formalism, and the plane-wave pseudopotential method. An analysis of the electronic structure with the help of electronic density of states shows that the density of states at the Fermi level (N (E-F) is found to be governed by the Mn 3d electrons with some contributions from the 2p states of 0 atoms. It is important to note that the contribution of Mn 3d states to N(E-F) is as much as 85%. From our phonon calculations, we have obtained that the main contribution to phonon density of states (below 250 cm(-1)) comes from the coupled motion of Mn and 0 atoms while phonon modes between 250 cm(-1) and 375 cm(-1) are characterized by the vibrations of all the three types of atoms. The contribution from Li increases rapidly at higher frequency (above 375 cm(-1)) due to the light mass of this atom. Finally, the specific heat and the Debye temperature at 300 K are calculated to be 249.29 J/mol K and 820.80 K respectively. (C) 2013 Elsevier Ltd. All rights reserved.
