[Wien] energy limit problems

Fecher, Gerhard fecher at uni-mainz.de
Fri Jul 28 08:47:34 CEST 2017


I wonder whether such an optimization makes sense at all,
this would optimize the volume of the vacuum, is it that what you want  ?

Ciao
Gerhard

DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
"I think the problem, to be quite honest with you,
is that you have never actually known what the question is."

====================================
Dr. Gerhard H. Fecher
Institut of Inorganic and Analytical Chemistry
Johannes Gutenberg - University
55099 Mainz
and
Max Planck Institute for Chemical Physics of Solids
01187 Dresden
________________________________________
Von: Wien [wien-bounces at zeus.theochem.tuwien.ac.at] im Auftrag von Yoji Kobayashi [yojik at scl.kyoto-u.ac.jp]
Gesendet: Freitag, 28. Juli 2017 08:25
An: wien at zeus.theochem.tuwien.ac.at
Betreff: [Wien] energy limit problems

Dear users,

I have been trying to optimize the volume for a Ti 111 slab and have run into problems (struct file attached at the end). The UG mentions the topic but I’m still not sure. Here’s the situation in short (I hope):

I first tried a volume optimization (using the built-in script) at -6.0, -4.0, -2.0, 0, +2.0, +4.0, and +6.0 % changes in lattice parameter, but got the error

 'SELECT' - no energy limits found for atom   2  L= 0
 'SELECT' - E-bottom    0.58302   E-top -200.00000

in lapw1.error. I wasn’t sure at which lattice parameter this had occurred, so ran a few of them as separate cases using the .struct files already generated. I didn’t test all 7, but here is what I got:

-6%: convergence in 54 SCF cycles, no error
-4%: convergence in 51 SCF cycles, no error
-2%: error as above at SCF cycle 16, with :E2_0001: E( 2)=   -0.3310   E(BOTTOM)=   -0.331   E(TOP)= -200.000  0 -1   165  (in *.output1).
0%: convergence in 51 cycles, no error
+2%: error in cycle 26,  with  'LAPW2' - semicore band-ranges too large, ghostbands ? (in lapw2.error)

I’m a bit confused as there is no trend with lattice parameters, but, now more details:

k-points: 15x15x1, RMT of Ti: 2, RKMax: 4, TEMP 0.002, mixing factor: 0,1;
lmax (.in1): 0.1, IFFT (.in0): set to 1.3, but gets changed to 2.0

These parameters are what I ended up after doing volume optimizations of a TiH2 slab of the same size. I eventually wish to compare nitrogen atom adsorption on Ti vs. TiH2 surfaces, so that is why I am starting with these parameters for the Ti case.

I understand that both error messages for the -2% and +2% are discussed in the trouble shooting section of manual. However, the problem is cannot be with differing RMTs here, and for the -2% case,  "QTL-B value" or 'ghost” does not appear in *.scf or *.output2, so ghost bands do not seem to be the problem. The SCF parameters (DIS, etc.) bounce a bit but they usually do for the convergent cases too. According to the manual, I should start playing with the energies in .in1, but how should I start? I would need to redo for all Ti and TiH2 structures, right? A little daunting, hence I’d like to ask for help first.

As for the +2% case, I do not see any QTL-B lines in *.output2. I haven’t got to examining the eigenvalues etc. yet, but first wanted to clear up the -2% case.

I can send the  -4%, -2%, and +2% case directories as zipped files if necessary. I’ve attached the  -2% .struct file below for reference.

Thanks,

Yoji
======
octavetmp
H   LATTICE,NONEQUIV.ATOMS:  5 164 P-3m1
MODE OF CALC=RELA unit=bohr
  5.537277  5.537277 83.436225 90.000000 90.000000120.000000
ATOM  -1: X=0.33333333 Y=0.66666667 Z=0.26280562
          MULT= 2          ISPLIT= 4
      -1: X=0.66666667 Y=0.33333333 Z=0.73719438
Ti1        NPT=  781  R0=.000050000 RMT=   2.00000   Z:  22.
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                     0.0000000 1.0000000 0.0000000
                     0.0000000 0.0000000 1.0000000
ATOM  -2: X=0.33333333 Y=0.66666667 Z=0.47364507
          MULT= 2          ISPLIT= 4
      -2: X=0.66666667 Y=0.33333333 Z=0.52635493
Ti2        NPT=  781  R0=.000050000 RMT=   2.00000   Z:  22.
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                     0.0000000 1.0000000 0.0000000
                     0.0000000 0.0000000 1.0000000
ATOM  -3: X=0.33333333 Y=0.66666667 Z=0.68448453
          MULT= 2          ISPLIT= 4
      -3: X=0.66666667 Y=0.33333333 Z=0.31551547
Ti3        NPT=  781  R0=.000050000 RMT=   2.00000   Z:  22.
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                     0.0000000 1.0000000 0.0000000
                     0.0000000 0.0000000 1.0000000
ATOM  -4: X=0.66666667 Y=0.33333333 Z=0.42093521
          MULT= 2          ISPLIT= 4
      -4: X=0.33333333 Y=0.66666667 Z=0.57906479
Ti4        NPT=  781  R0=.000050000 RMT=   2.00000   Z:  22.
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                     0.0000000 1.0000000 0.0000000
                     0.0000000 0.0000000 1.0000000
ATOM  -5: X=0.66666667 Y=0.33333333 Z=0.63177466
          MULT= 2          ISPLIT= 4
      -5: X=0.33333333 Y=0.66666667 Z=0.36822534
Ti5        NPT=  781  R0=.000050000 RMT=   2.00000   Z:  22.
LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
                     0.0000000 1.0000000 0.0000000
                     0.0000000 0.0000000 1.0000000
  12      NUMBER OF SYMMETRY OPERATIONS
 1 0 0 0.00000000
 0 1 0 0.00000000
 0 0 1 0.00000000
       1
 0-1 0 0.00000000
 1-1 0 0.00000000
 0 0 1 0.00000000
       2
-1 1 0 0.00000000
-1 0 0 0.00000000
 0 0 1 0.00000000
       3
 0 1 0 0.00000000
 1 0 0 0.00000000
 0 0-1 0.00000000
       4
 1-1 0 0.00000000
 0-1 0 0.00000000
 0 0-1 0.00000000
       5
-1 0 0 0.00000000
-1 1 0 0.00000000
 0 0-1 0.00000000
       6
-1 0 0 0.00000000
 0-1 0 0.00000000
 0 0-1 0.00000000
       7
 0 1 0 0.00000000
-1 1 0 0.00000000
 0 0-1 0.00000000
       8
 1-1 0 0.00000000
 1 0 0 0.00000000
 0 0-1 0.00000000
       9
 0-1 0 0.00000000
-1 0 0 0.00000000
 0 0 1 0.00000000
      10
-1 1 0 0.00000000
 0 1 0 0.00000000
 0 0 1 0.00000000
      11
 1 0 0 0.00000000
 1-1 0 0.00000000
 0 0 1 0.00000000
      12


==========================================================
Yoji Kobayashi, Junior Assoc. Prof.       yojik at scl.kyoto-u.ac.jp<mailto:yojik at scl.kyoto-u.ac.jp>
http://www.scl.kyoto-u.ac.jp/~yojik/index.htm

Kageyama Group, Dept. of Energy and Hydrocarbon Chemistry
Graduate School of Engineering, Kyoto University
Nishikyo-ku, Kyoto 615-8510, Japan

Tel.: +81-75-383-2509     Fax: +81-75-383-2510
http://www.ehcc.kyoto-u.ac.jp/eh10/kageyama.html
==========================================================



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