Dear Yambo developers,

In GoWo calculations the gap was opened by almost 0.10 eV but the subsequent GW (G1W1 on top of G0W0) resulted in the negative corrections of 0.46 eV resulting in to decrease in the gap!! This was not what I was expecting. The calculations include SOC effects while I also decreased the band range in QPkrange slightly in the G1W1 calculations (but still including plenty of bands around Fermi). The inputs are also attached herein. Can you please suggest what I might be doing wrong here?

This is the result of the report from the G2W2 (when reading G1W1 ndb.QP database)

Code: Select all

```
[04] External/Internal QP corrections
=====================================
[RD././G1W1/ndb.QP]-------------------------------------------------------------
Lattice constants : 10.49403 31.75089 10.56345
Coulomb cutoff potential : none
Electronic Temperature : 300.1998 [K]
Bosonic Temperature : 300.0997 [K]
Green`s function energies : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
wavefunctions : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
PPA diel. fun. energies : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
wavefunctions : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
QP tot states : 2400
GWo SC iterations : 0
GW SC iterations : 0
GW solver : Newton
GW approximation : PPA
PPA imaginary Energy : 27.21138 ev
GW SC iterations : 0
dS/dw steps : 2
dS/dw step : 0.100000 ev
X G`s : 695 used
X G`s : 695 disk
X bands : 1 1000
X poles : 100.0000 o/o
X e/h E range : -1.000000 -1.000000 ev
X xc-Kernel : none
X BZ energy Double Grid : no
Sc/G bands : 1 1000
Sc/G damping : 0.100000 ev
Sc bands terminator : no
Sx RL components : 5353
QP @ state[ 1 ] K range : 1 40
QP @ state[ 1 ] b range : 347 406
GF energies kind : E < ./gw_conv-20EXX_80VXX_40FFTG_bands1-1000_5NGBklx/ndb.QP + E Fit
GF WF`s kind : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
Xs energies kind : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
Xs WF`s kind : Perdew, Burke & Ernzerhof(X)+Perdew, Burke & Ernzerhof(C)
- S/N 009346 ---------------------------------------------- v.05.00.02 r.19567 -
E<./G1W1/ndb.QP[ PPA@E 27.21138 = XG 695 = Xb 1-1000 = Scb 1-1000]
[dE_from_DB-Nearest K] Exact matches : 100.0000 [o/o]
[04.01] FIT on E < ./G1W1/ndb.QP
================================
= FIT report for E<./G1W1/ndb.QP[ PPA@E 27.21138 = XG 695 = Xb 1-1000 = Scb 1-1000] =
= First column (conduction), Second column (valence) =
Gap correction (database) : -0.461772 [eV]
(FIT, actual) : 0.184843 [eV]
Energies 0th order : 0.564467 0.841396 [eV]
Energies 1st order : 1.018448 0.838082
Error: 0.002501 0.003491
[QP_apply] Action to be applied: E<./G1W1/ndb.QP[ PPA@E 27.21138 = XG 695 = Xb 1-1000 = Scb 1-1000]
[05.01] QP corrections report
==============================
[X+QP] === General ===
[X+QP] Electronic Temperature : 0.258779E-1 300.300 [eV K]
[X+QP] Bosonic Temperature : 0.258606E-1 300.100 [eV K]
[X+QP] Finite Temperature mode : yes
[X+QP] El. density : 0.72091E+24 [cm-3]
[X+QP] Fermi Level : 0.797699 [eV]
[X+QP] === Gaps and Widths ===
[X+QP] Conduction Band Min : 0.856257 [eV]
[X+QP] Valence Band Max : -0.906222 [eV]
[X+QP] Filled Bands : 376
[X+QP] Empty Bands : 377 1000
[X+QP] Direct Gap : 1.802209 [eV]
[X+QP] Direct Gap localized at k-point : 9
[X+QP] Indirect Gap : 1.762479 [eV]
[X+QP] Indirect Gap between k-points : 1 9
[X+QP] Last valence band width : 0.510743 [eV]
[X+QP] 1st conduction band width : 1.274906 [eV]
[coarse-grid] Minimum Bare Gap [ev]: 2.224229
[coarse-grid] Minimum Gap Correction [ev]: -0.461750
```

Thanks,

PS (after post): It seems like a similar issue was reported here earlier too!

viewtopic.php?f=30&t=2002&p=10308&hilit ... +GW#p10308
I'm not sure whether the parallelization problem exists also in v5.0.2 or not!

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