The FPLO^{®} package is a full-potential local-orbital minimum-basis code [1] [2] to solve the Kohn-Sham equations on a regular lattice [6]. The situation of a chemically disordered structure is covered by a CPA solver [3], relativistic effects can be treated in a related 4-component code [4], and the LSDA+U formalism is implemented [5].

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 [7]. 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.

- References
- [1] K. Koepernik and H. Eschrig, Phys. Rev. B 59, 1743 (1999);
[2] I. Opahle, K. Koepernik, and H. Eschrig, Phys. Rev. B 60, 14035 (1999).

[3] K. Koepernik, B. Velicky, R. Hayn, and H. Eschrig, Phys. Rev. B 55, 5717 (1997).

[4] H. Eschrig, M. Richter, I. Opahle, Relativistic Solid State Calculations, in: Relativistic Electronic Structure Theory, Part 2. Applications (P. Schwerdtfeger, ed.), Theoretical and Computational Chemistry, vol.13, Elsevier, 2004, pp.723–776.

[5] H. Eschrig, K. Koepernik, and I. Chaplygin, J. Solid State Chemistry 176, 482 (2003).

[7] K. Lejaeghere

*et al.*, Science**351**, 1415-U81 (2016).

Financial support by MPG, DFG, Humboldt-Foundation and BMBF is gratefully acknowledged.