### Author Topic: problems with SCF energy convergence in COSMO  (Read 10180 times)

#### e.berardo

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##### problems with SCF energy convergence in COSMO
« on: March 15, 2013, 12:07:24 PM »
Hi all,
I have been running some COSMO geometry optimizations in DFT for two clusters of transition metal oxides.
For the bigger structure (~100 atoms) I didn't experience any problem, as the gradient decreases the SCF energy goes towards convergence.
For the smaller structure (~24 atoms) I am observing something really strange. After many steps the gradients are very small and the geometry is not changing anymore, but the SCF energy is jumping up and down, with no sign of convergence.

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`      ******************************************************************                           CONVERGENCE INFORMATION                               Converged?     Value      Criterion             Energy change         no       1.2181215   0.0000010             RMS of displacement   yes      0.0000004   0.0005000             RMS of gradient       yes      0.0000000   0.0005000             MAX displacement      yes      0.0000027   0.0010000             MAX gradient          yes      0.0000000   0.0001000      ****************************************************************** `
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`   cycle =    245    SCF energy =    -4409.7166469090   |dE/dxyz| =  0.000088  cycle =    246    SCF energy =    -4405.0600362230   |dE/dxyz| =  0.000088  cycle =    247    SCF energy =    -4410.9270409740   |dE/dxyz| =  0.000087  cycle =    248    SCF energy =    -4416.0999436860   |dE/dxyz| =  0.000087  cycle =    249    SCF energy =    -4405.0069743620   |dE/dxyz| =  0.000087  cycle =    250    SCF energy =    -4418.2815994030   |dE/dxyz| =  0.000087  cycle =    251    SCF energy =    -4414.5429156850   |dE/dxyz| =  0.000087  cycle =    252    SCF energy =    -4415.8180561870   |dE/dxyz| =  0.000087  cycle =    253    SCF energy =    -4419.6058398660   |dE/dxyz| =  0.000087`
Just for the sake of argument I checked the OC corrected energy as well, but I see the same behavior:
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`job.94:    Total energy + OC corr. =    -4415.7873333840job.95:    Total energy + OC corr. =    -4400.1291837066job.96:    Total energy + OC corr. =    -4419.1704658379job.97:    Total energy + OC corr. =    -4400.2408475728job.98:    Total energy + OC corr. =    -4415.5401379877job.99:    Total energy + OC corr. =    -4403.7589587977job.last:    Total energy + OC corr. =    -4415.7982812745`
The setup for the two calculations was the same, both jobs are parallel (8 processors), but running on different machines (both linux64). Version of turbomole 6.4
I am using the default values for COSMO, with the only exception of the epsilon value (80) and the element radii for O and H are the optimized ones, while for Ti the default one.

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` ==============================================================================                                  COSMO RESULTS ==============================================================================  PARAMETER:    nppa:      1082    nspa:        92    nsph:        32    nps:        957    npspher:    436    disex:   10.0000        disex2:  3918.79        rsolv [A]: 1.3000    routf:     0.8500    phsran:    0.0        ampran:   0.10E-04    cavity:  closed    epsilon:    80.000    refind:     1.300    fepsi:      0.9813665  CAVITY VOLUME/AREA [a.u.]:    surface: V1.0, A matrix: V1.0    area:   916.62    volume:  1874.76  SCREENING CHARGE:    cosmo      :  -0.035792    correction :   0.033567    total      :  -0.002226  ENERGIES [a.u.]:    Total energy            =    -4414.5767535569    Total energy + OC corr. =    -4414.5801598139    Dielectric energy       =       -0.0901258038    Diel. energy + OC corr. =       -0.0935320608  ELEMENT RADIUS [A]: ATOM LIST    h  1.30: 1,2,4,5,19,21,22,24    o  1.72: 3,6,11-18,20,23    ti 2.22: 7-10 ==============================================================================`

Has somebody previously experienced this behaviour? Or is there something wrong in my setup?

Enrico

#### uwe

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##### Re: problems with SCF energy convergence in COSMO
« Reply #1 on: March 17, 2013, 09:50:21 PM »
Hi Enrico,

this does indeed look very strange. If the energy changes that much but the gradients should do not, the coordinates would have to change a lot.

Could you try to run the same input in serial mode rather than parallel?

And, please, send the input and the output to the Turbomole support by email (turbomole at cosmologic.de), because it has to be checked where this behavior comes from.

Regards,

Uwe

#### e.berardo

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##### Re: problems with SCF energy convergence in COSMO
« Reply #2 on: March 18, 2013, 03:27:03 PM »
I am running the serial job at the moment, and I'll let you know what's my progress with that, anyway I also contacted the support team.

Cheers,
Enrico

#### mario8eren

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##### Re: problems with SCF energy convergence in COSMO
« Reply #3 on: October 01, 2014, 12:40:32 PM »
I am running the serial job at the moment, and I'll let you know what's my progress with that, anyway I also contacted the support team.

Have you figured out the solution to this problem? I am having similar issues.

Mario

#### uwe

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##### Re: problems with SCF energy convergence in COSMO
« Reply #4 on: October 01, 2014, 02:50:34 PM »
Hi,

if you are still using Turbomole version 6.4 and run COSMO MPI parallel jobs, make sure to update to version 6.4.1 or newer.  See: http://www.turbo-forum.com/index.php/topic,812.0.html

Uwe

#### mario8eren

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##### Re: problems with SCF energy convergence in COSMO
« Reply #5 on: October 02, 2014, 12:09:56 PM »
Hi,

if you are still using Turbomole version 6.4 and run COSMO MPI parallel jobs, make sure to update to version 6.4.1 or newer.  See: http://www.turbo-forum.com/index.php/topic,812.0.html

Uwe

Thank you very much.

Mario