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PAW+DFPT+GGA has unreasonable energy values

Posted: Wed Jun 09, 2021 7:01 pm
by gswylq
Dear everyone,

I calculate the Se2Mo elastic constants and piezoelectric properties using the PAW+DFPT+GGA(Se.GGA_PBE-JTH.xml,Mo.GGA_PBE-JTH.xml). However the results give some unreasonable energy values as below. The errors are also reported in the forums (viewtopic.php?f=10&t=3975) and not solved。


Please give me some suggestions. Thank you.

Qiang Li

########################
iteration_state: {dtset: 3, }
solver: {iscf: 7, nstep: 40, nline: 4, wfoptalg: 10, }
tolerances: {toldfe: 1.00E-12, }
...

iter 2DEtotal(Ha) deltaE(Ha) residm vres2
-ETOT 1 -701760.65247417 -6.984E+05 3.645E+01 2.897E+17
ETOT 2 -49209390380.263 -4.921E+10 7.120E+05 2.045E+22
ETOT 3 -10552868127.241 3.866E+10 8.377E+05 1.082E+22
ETOT 4 -765158638.97658 9.788E+09 1.616E+05 1.174E+21
ETOT 5 -328606905.80232 4.366E+08 2.190E+05 2.164E+20
ETOT 6 -285982265.96698 4.262E+07 2.339E+04 1.552E+20
ETOT 7 -126967387.93959 1.590E+08 5.587E+04 7.697E+19
ETOT 8 -53706375.221736 7.326E+07 1.250E+04 2.930E+19
ETOT 9 -57720945.789142 -4.015E+06 2.587E+04 3.018E+19
ETOT 10 -94194367867.836 -9.414E+10 1.713E+07 3.913E+22
ETOT 11 -384991891410.32 -2.908E+11 6.568E+07 1.496E+23
ETOT 12 -36551214042.881 3.484E+11 2.122E+07 4.576E+22
ETOT 13 -205481270109.56 -1.689E+11 5.039E+06 9.851E+22
ETOT 14 -89283335120.502 1.162E+11 1.997E+07 6.265E+22
ETOT 15 -803690232494.15 -7.144E+11 9.567E+06 3.450E+23
ETOT 16 -450853856217.79 3.528E+11 3.788E+07 2.767E+23
ETOT 17 -2121346612896.9 -1.670E+12 3.431E+08 8.809E+23
ETOT 18 -7.34499723495663E+14 -7.324E+14 4.176E+10 3.065E+26
ETOT 19 -5.63337223721916E+14 1.712E+14 1.541E+11 3.093E+26
ETOT 20 -1.82127807321210E+14 3.812E+14 6.711E+10 9.866E+25
ETOT 21 -1.38585260115070E+15 -1.204E+15 1.148E+11 5.971E+26
ETOT 22 -1.85799200262427E+15 -4.721E+14 9.617E+10 8.497E+26
ETOT 23 -1.22152216435784E+16 -1.036E+16 4.086E+11 5.449E+27
ETOT 24 -4.72721586153121E+16 -3.506E+16 6.590E+11 2.157E+28
ETOT 25 -1.13397096852396E+17 -6.612E+16 3.492E+12 4.856E+28
ETOT 26 -1.56161417490567E+19 -1.550E+19 3.997E+14 6.457E+30
ETOT 27 -1.52792414370269E+18 1.409E+19 4.666E+14 1.734E+30
ETOT 28 -3.27796815393749E+18 -1.750E+18 1.481E+15 1.566E+30
ETOT 29 -5.63493846164628E+19 -5.307E+19 1.581E+16 2.231E+31
ETOT 30 -4.66932036183611E+19 9.656E+18 7.006E+15 2.440E+31
ETOT 31 -8.28079591771165E+20 -7.814E+20 2.533E+16 3.597E+32
ETOT 32 -4.75626230752273E+21 -3.928E+21 1.053E+17 2.005E+33
ETOT 33 -6.93628489422145E+21 -2.180E+21 1.750E+17 3.311E+33
ETOT 34 -5.71010084387757E+22 -5.016E+22 4.875E+18 2.420E+34
ETOT 35 -1.37611319784882E+22 4.334E+22 3.745E+18 1.049E+34
ETOT 36 -2.12580639293762E+23 -1.988E+23 1.409E+19 8.999E+34
ETOT 37 -1.86232926681585E+24 -1.650E+24 2.852E+20 7.471E+35
ETOT 38 -1.97315995886578E+24 -1.108E+23 6.801E+20 1.054E+36
ETOT 39 -9.26233829865064E+25 -9.065E+25 3.149E+21 3.864E+37
ETOT 40 -1.63474793427571E+26 -7.085E+25 2.236E+21 7.441E+37

Re: PAW+DFPT+GGA has unreasonable energy values

Posted: Thu Jun 10, 2021 12:47 pm
by mmazdz
1. Currently a ABINIT is only available PAW+DFPT+LDA
2. If you want a DFPT+GGA you need NC pseudopotential
3. For 2D structures there is a problem even with PAW+DFPT+LDA, NC pseudopotentials work correctly

Re: PAW+DFPT+GGA has unreasonable energy values

Posted: Fri Jun 11, 2021 2:37 pm
by zanto
mmazdz wrote: ↑
Thu Jun 10, 2021 12:47 pm
1. Currently a ABINIT is only available PAW+DFPT+LDA
2. If you want a DFPT+GGA you need NC pseudopotential
3. For 2D structures there is a problem even with PAW+DFPT+LDA, NC pseudopotentials work correctly
Hello,

I am trying to compute surface energy of carbon diamond structure (111) using PAW pseudopotential taken from http://www.pseudo-dojo.org/ (Type PAW (JTH v1.0), XC PBE). Everything is ok until I have 18 layers of C(111) or more with vacuum (does not matter how many angstroms of vacuum). Every computation is then oscillating and diverging. The same issue is also for WC(0001) in hexagonal structure with same type of pseudopotential. Everything works fine for both structures with NC SR (ONCVPSP v0.4.1), XC PBE pseudopotencial. Input file is attached.

This is not DFTP simulation but is this problem the same as discussed here?

Thank you for any suggestions
zanto

Re: PAW+DFPT+GGA has unreasonable energy values

Posted: Mon Jun 21, 2021 12:32 pm
by mmazdz
What I would do
1. Start with LDA+PAW
2. Check other PAW pseudopotential https://www.physics.rutgers.edu/gbrv/
3. I would reduce ecut to 500 eV (for PAW 800 eV somewhat redundant)
4. Try occopt = 3 tsmear =0.01
5. "ngkpt 12 12 1" Is that so much needed? I always use kptrlen~35 https://docs.abinit.org/variables/gstate/#kptrlen
6. Generate own PAW http://users.wfu.edu/natalie/papers/pwpaw/man.html
7. Use NC pseudopotential