[Wien] Large charge fluctuation in hybrid calculations

[Atta-fynn, Raymond]

Dear Users,

I am performing non-magnetic calculations on a metal slab using hybrid DFT (with TEMP smearing). I have been able to converge 1-7 layers and 9-layer thick slabs with no serious problems. For some reason the 8-layer slab does not want to converge. The charge density oscillates with large amplitudes and eventually the job crashes. Calculations were performed the standard way:

runsp_c_lapw -ec 0.00001 -cc 0.001 -i 300 -p
runsp_c_lapw -ec 0.00001 -cc 0.001 -i 300 -p -so
runsp_c_lapw -ec 0.00001 -cc 0.001 -i 300 -p -so -eece

The problem begins in step 1 (NSO calculations). I've pulled all  the standard tricks (reduce mixing, etc.) but the problem will just not go away. The first few cycles for the charge distance looks like:

:DIS  :  CHARGE DISTANCE       ( 3.0623129 for atom    2 spin 2)      4.8323633
:DIS  :  CHARGE DISTANCE       ( 3.7525968 for atom    8 spin 2)      4.8109130
:DIS  :  CHARGE DISTANCE       ( 4.5335108 for atom    4 spin 2)      4.7597241
:DIS  :  CHARGE DISTANCE       ( 5.1545071 for atom    8 spin 2)      4.9702637
:DIS  :  CHARGE DISTANCE       ( 5.0675077 for atom    1 spin 2)      4.8569369
:DIS  :  CHARGE DISTANCE       ( 4.9684119 for atom    1 spin 2)      4.7391195
:DIS  :  CHARGE DISTANCE       ( 4.3727780 for atom    1 spin 2)      4.3237943
:DIS  :  CHARGE DISTANCE       ( 3.7769948 for atom    4 spin 2)      4.8503262
:DIS  :  CHARGE DISTANCE       ( 3.3436987 for atom    4 spin 2)      3.8495739
:DIS  :  CHARGE DISTANCE       ( 3.2228522 for atom    1 spin 2)      5.1590833
:DIS  :  CHARGE DISTANCE       ( 2.7148248 for atom    7 spin 2)      3.7982418
:DIS  :  CHARGE DISTANCE       ( 3.3313579 for atom    7 spin 2)      4.5302253
:DIS  :  CHARGE DISTANCE       ( 3.3598285 for atom    4 spin 2)      5.0925813
:DIS  :  CHARGE DISTANCE       ( 2.9529033 for atom    4 spin 2)      5.2109088
:DIS  :  CHARGE DISTANCE       ( 3.3483133 for atom    4 spin 2)      5.0412665
:DIS  :  CHARGE DISTANCE       ( 2.9641391 for atom    7 spin 2)      4.8027516
:DIS  :  CHARGE DISTANCE       ( 3.1663445 for atom    4 spin 2)      4.7292585
:DIS  :  CHARGE DISTANCE       ( 3.2054421 for atom    5 spin 2)      3.9307946
:DIS  :  CHARGE DISTANCE       ( 3.1672886 for atom    5 spin 2)      4.4866535
:DIS  :  CHARGE DISTANCE       ( 3.2654575 for atom    1 spin 2)      5.0048377
:DIS  :  CHARGE DISTANCE       ( 3.1100926 for atom    5 spin 2)      4.2558609
Any suggestions would be appreciated.

Thank you.
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