Adding Elk-TRIQS interface (first iteration)
This interface reads in Elk's ground-state files / projectors generated by a specific Elk interface code version (https://github.com/AlynJ/Elk_interface-TRIQS). The interface can perform charge-self consistent DFT+DMFT calculations using the aforementioned Elk code version, including spin orbit-coupling. Hence, this is the first open source interfaced DFT code to triqs with FCSC support.
The commit includes detailed documentation and tutorials on how to use this interface. Moreover, further new post-processing routines are added for Fermi surface plots and spectral functions (A(w)) from the elk inputs.
The interface was tested by A. James and A. Hampel. However, this is the first iteration of the interface and should be used with care. Please report all bugs.
List of changes:
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- sumk.py: added cacluation of charge density correction for elk (dm_type='elk').
- sumk_dft_tools.py: added new post-processing functions to calculate the Fermi surface and A(w) from the Elk inputs.
- documentation and tutorial files amended for this interface.
- added python tests for the Elk converter.
