LSELFENERGY
LSELFENERGY = [logical]
Default: LSELFENERGY = .FALSE.
Description: Controls whether the frequency-dependent self-energy is calculated or not.
If LSELFENERGY=.FALSE., QP shifts are evaluated. This is the default behavior.
If LSELFENERGY=.TRUE., the frequency dependent self-energy is evaluated and printed to vasprun.xml. An example output looks like the following:
<varray name="selfenergy" > <v> -150.00000000 -25.40060536 0.24429448 </v> <v> -149.70000000 -25.40600800 0.24673910 </v> <v> -149.40000000 -25.41141065 0.24918372 </v> <v> -149.10000000 -25.41681330 0.25162834 </v> <v> -148.80000000 -25.42221682 0.25406890 </v> <v> -148.50000000 -25.42762671 0.25647992 </v> <v> -148.20000000 -25.43303731 0.25888834 </v>
If quartic-scaling GW algorithms are selected, e.g. ALGO=EVGW0, the first column corresponds to points on the real-frequency axis. The second and third column are the real and imaginary parts of the self-energy at a given k-point and band index. In this case the evaluation of QP shifts is also bypassed and a small set of self-energy points are printed to OUTCAR instead, similar to the following output
calculating selfenergy CALC_SELFENERGY_LINEAR between w=-150.00 150.00
k-point 1 : 0.0000 0.0000 0.0000
band No. band energies occupation
1 -11.7125 2.00000 selfenergy along real axis
-150.0000000 -25.4006054 0.2442945
-147.0000000 -25.4546849 0.2685030
-144.0000000 -25.5088867 0.2923888
-141.0000000 -25.5724017 0.3182992
-138.0000000 -25.6566991 0.3488243
For low-scaling GW algorithms, the QP-energies are evaluated and printed to OUTCAR. In contrast, the vasprun.xml file now contains the self-energy on the imaginary frequency axis for the points selected by the Minimax routines.[1]
Related tags and articles
- for a practical guide to GW calculations
- ALGO for response functions and RPA calculations
- LFINITE_TEMPERATURE finite temperature formalism
- NOMEGA number of real or imaginary frequency points