Large scale quantum transport within the optimal basis density matrix minimization approach

Many ab initio methods for computing the total energy of atomic systems make use of non-orthogonal localized functions to expand the wave-functions and the density matrix. These are usually taken as localized atom-centered functions, such as numerical or Gaussian atomic orbitals. In the optimal basis density-matrix minimization (OBDM) approach, the localized support functions are fully optimized during the calculation so as to minimise the energy functional. In this presentation, the linear-scaling OBDM approach is first reviewed. Then, the use of optimized support functions for large-scale electronic transport calculations is discussed.