Calculation of the configurational energy density of states for Li0.5La0.5TiO3 utilizing first principles optimizations and a new Wang and Landau algorithm variant.

In this work a new variant of the Wang and Landau algorithm for calculation of the configurational energy density of states is presented and applied to the 2d Ising model and to density functional theory simulations of the disordered solid state lithium ion conductor Li0.5La0.5TiO3. Tests reveal that the algorithm has good performance and in particular at short iteration. The application of the algorithm to the Li0.5La0.5TiO3 system is an exploration into the disordered nature of the material along with a benchmark into what level of configurational sampling is currently feasible with density functional theory methods. Along with the detailed computational results some mathematical arguments are presented that the algorithm is convergent. The algorithm developed is naturally parallel and is referrred to as B_LENDER for B_Lend Each New Density Each Round.