Spex Manual

Spex is a computer code based on many-body perturbation theory. It uses the all-electron full-potential linearized augmented plane-wave method (FLAPW), which provides an accurate basis set for all kinds of materials including transition metals, oxides, and even f-electron systems.

Currently Spex can calculate quasiparticle properties (one-shot and self-consistent) using the GW approximation, EELS and optical spectra as well as total energies in the RPA approximation, and spin-wave spectra from the Bethe-Salpeter equation. (TDDFT is implemented but unmaintained at the moment.)

It needs input from a converged DFT calculation, which can be generated by Fleur but also by any other FLAPW-DFT code.

If you use Spex for your research, please cite the following work:

Christoph Friedrich, Stefan Blügel, Arno Schindlmayr, “Efficient implementation of the GW approximation within the all-electron FLAPW method”, Phys. Rev. B 81, 125102 (2010).