mirror of
https://github.com/triqs/dft_tools
synced 2024-12-28 23:25:56 +01:00
44 lines
1.8 KiB
ReStructuredText
44 lines
1.8 KiB
ReStructuredText
|
.. highlight:: python
|
||
|
|
|
||
|
|
#######################
|
||
|
|
Charge self-consistency
|
||
|
|
#######################
|
||
|
|
|
||
|
|
Introduction
|
||
|
|
************
|
||
|
|
|
||
|
|
Running a DFT+DMFT calculation in the charge self-consistent mode
|
||
|
|
requires additional process management whereby the control is given
|
||
|
|
to the VASP and to the TRIQS code in an alternating manner.
|
||
|
|
It is implemented by a lock system. A VASP process is launched in
|
||
|
|
the background and a self-consistency (SC) script in the foreground.
|
||
|
|
Once VASP reaches the point where the projectors are generated
|
||
|
|
it creates a lock file `vasp.lock` and waits until the lock file is
|
||
|
|
removed. The SC script, in turn, waits for the VASP process and once
|
||
|
|
the lock file is created it starts a DMFT iteration. The DMFT iteration
|
||
|
|
must finish by generating a Kohn-Sham (KS) density matrix (file `GAMMA`)
|
||
|
|
and removing the lock file. The VASP process then reads in `GAMMA`
|
||
|
|
and proceeds with the next iteration.
|
||
|
|
|
||
|
|
The DMFT iteration is performed using a user-defined script.
|
||
|
|
However, the control part is maintained by two universal scripts:
|
||
|
|
`sc_dmft.sh` and `sc_dmft.py`.
|
||
|
|
|
||
|
|
The first script, `sc_dmft.sh`, launches the VASP process
|
||
|
|
in the background mode, takes its pid, and launches `sc_dmft.py`
|
||
|
|
in the foreground mode.
|
||
|
|
Both processes are run within an MPI environment with an appropriate
|
||
|
|
number of MPI nodes.
|
||
|
|
|
||
|
|
The second script, `sc_dmft.py`, is responsible for the charge self-consitency
|
||
|
|
logic described in the first paragraph. It also combines the total
|
||
|
|
energy contributions coming from the DFT and DMFT parts.
|
||
|
|
The script imports a user-defined DMFT script `dmft_cycle.py` which
|
||
|
|
must produce KS density-matrix file `GAMMA` for the next DFT iteration
|
||
|
|
and also must return the correlation (including the double counting) energy
|
||
|
|
of the impurity model as well as a correlation correction to the
|
||
|
|
DFT band energy (resulting from the difference between the bare
|
||
|
|
and DMFT density matrices).
|
||
|
|
|
||
|
|
|