The FPLO® package is a full-potential local-orbital code   to solve the Kohn-Sham equations  on a regular lattice or with free boundary conditions (finite systems). Relativistic effects are treated either in a scalar-relativistic or a full 4-component formalism . Available functionals are LSDA, GGA (PBE 96) and LSDA/GGA+U. . Orbital polarization correction can be applied.
Much effort has been spent to achieve a level of numerical accuracy which is comparable to advanced full-potential LAPW implementations, though the basis set is considerably smaller . This makes highly accurate full-potential calculations for elementary cells of up to 300 atoms feasible on single-CPU machines and is a good starting point for approaches beyond standard DFT.
The FPLO band structure can be wannierized , which allows model extraction and post processing, in particular the calculation of topological properties, topological surface states, dHvA spectra and more using the in-build PYTHON interface (pyfplo).
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Financial support by MPG, DFG, Humboldt-Foundation, EC and BMBF is gratefully acknowledged.