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Grimme D3 dispersion correction (IVDW = 11 or 12) is failing on a very simple molecule, XeF2, even though the same system is well behaved using no dispersion, Grimme D2 (IVDW = 10), or Tkatchenko-Scheffler (IVDW = 20) dispersion correction. After the first iteration in the D3 calculation (which converges), the DFTD3 output contains many errors, as indicated by the lines of asterisks in the output below. These errors (apparently) cause the next ionic step to fail with a variety of errors (e.g., BRMIX problems, internal error SETYLM_AUG). This problem occurs with both PBE and revPBE calculations and various tweaks of the INCAR. In contrast, the other calculations (no dispersion, etc.) behave normally.

The output and input information is given below.

—————————— Sample Failing DFTD3 Output (from OUTCAR) ————————————————

DFTD3 V3.0 Rev 1
IVDW = 12
DF revpbe
parameters
VDW_S6 = 1.0000
VDW_S8 = 2.3550
VDW_A1 = 0.5238
VDW_A2 = 3.5016
k1-k3 = 16.0000 1.3333 -4.0000
VDW_RADIUS = 50.2022 A
VDW_CNRADIUS = 21.1671 A
Edisp (eV)***********

E6 (eV) :***********
E8 (eV) : -0.0011
% E8 : -0.00
FORVDW: cpu time 0.0106: real time 0.0109

FORCE on cell =-STRESS in cart. coord. units (eV):
Direction XX YY ZZ XY YZ ZX
--------------------------------------------------------------------------------------
Alpha Z 1.77943 1.77943 1.77943
Ewald 733.46071 -157.91263 -157.91263 0.00000 0.00000 0.00000
Hartree 961.56183 485.89794 485.89836 0.00003 -0.00026 -0.00000
E(xc) -112.64288 -115.56697 -115.56698 0.00000 0.00000 0.00001
Local -1855.56228 -533.39692 -533.39742 -0.00007 0.00032 0.00001
n-local -165.40828 -182.50882 -182.50872 0.00046 0.00010 -0.00015
augment 56.60929 64.36377 64.36374 0.00002 0.00009 0.00002
Kinetic 389.88270 435.16895 435.16829 -0.00002 0.00035 0.00003
Fock 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
vdW ************************************************************************
-------------------------------------------------------------------------------------
Total ************************************************************************
in kB ************************************************************************
external pressure = *********** kB Pullay stress = 0.00 kB

—————————— INCAR ————————————————
VDW_SR = 0.923
SIGMA = 0.05
EDIFFG = -0.02
LREAL = False
IDIPOL = 4 # Removing the dipole correction has no effect
LWAVE = .FALSE.
LDIPOL = .TRUE.
IBRION = 1
ALGO = Fast
PREC = Normal # Use Accurate for T-S dispersion
IVDW = 11 # Change for different dispersion calculations
ISMEAR = 0
ISYM = 0
NELM = 60
DIPOL = 0.5 0.5 0.5
EDIFF = 1e-05
POTIM = 0.5
GGA = RE
ISIF = 2
NELMIN = 5
LCHARG = .FALSE.
NSW = 60

—————————— POSCAR ————————————————
F Xe
1.0000000000000000
18.8780000000000001 0.0000000000000000 0.0000000000000000
0.0000000000000000 15.0000000000000000 0.0000000000000000
0.0000000000000000 0.0000000000000000 15.0000000000000000
2 1
Cartesian
7.5000000000000000 7.5000000000000000 7.5000000000000000
11.3780000000000001 7.5000000000000000 7.5000000000000000
9.4390000000000001 7.5000000000000000 7.5000000000000000

—————————— KPOINTS ————————————————
KPOINTS created by Atomic Simulation Environment
0
Monkhorst-Pack
1 1 1
0.0 0.0 0.0

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