From NWChem
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4:02:52 AM PST  Fri, Feb 26th 2016 

Dear all, i'm facing either very serious lack in my theory background or compilation/nwchem problem. I did several calculations and just recently i noticed very strange thing (i checked three different calculations)  see part of my output below:
Total DFT energy = 1144.144378448133
One electron energy = 5654.477100400897
Coulomb energy = 2607.095668751906
ExchangeCorr. energy = 156.929943044225
Nuclear repulsion energy = 2058.598637126281
Numeric. integr. density = 178.000323079243
when you sum all the energies you get different number (?1145.7127...) than the one reported in Total DFT energy.
i've got this in all three calculations (probably all of them). Also, the difference in reported and "summed" energy is always different, approximately ~1.2 to 1.7 Hartrees. This is the input corresponding to the upper energies:
start dimerBO4MM1c33_GOB3LYP321G
MEMORY stack 2600 heap 500 global 800 mb
title "betaO4dimer in ccl4, initial structure from oBabel weighted conf search (MM1)  c33, geometry optimization B3LYP 321G"
geometry units an print xyz autosym
H 1.09605 2.24257 1.90815
C 1.41847 2.08854 0.87674
C 1.84098 3.17525 0.07199
O 1.81819 4.39938 0.71640
C 2.26350 2.93298 1.25811
O 2.79497 3.97266 1.98226
C 2.10800 1.64323 1.80510
O 2.33657 1.45588 3.14564
C 1.74719 0.58915 0.97642
H 1.73301 0.42869 1.34122
C 1.39752 0.79060 0.35917
C 0.90359 0.40502 1.15331
C 0.54163 0.75608 0.75684
H 1.16737 0.14184 0.68909
O 1.10710 1.65905 1.73269
H 0.49837 1.18660 0.24421
C 2.06553 2.54149 1.28458
C 3.01765 3.05298 2.19910
O 2.94863 2.67755 3.52330
C 4.00905 3.94736 1.72167
H 4.75432 4.37610 2.37384
C 4.06928 4.30063 0.38461
H 4.84743 4.97387 0.04043
C 3.11615 3.83955 0.49294
H 3.13149 4.13319 1.53682
C 2.10145 2.99245 0.04157
H 1.34790 2.73593 0.77732
C 1.89481 0.23345 3.71973
C 3.84170 3.67014 2.90678
C 1.63138 5.56450 0.09157
H 0.73470 5.46345 0.71315
H 1.48749 6.43465 0.55333
H 2.51469 5.79038 0.69721
H 3.54935 4.04304 3.89421
H 4.75448 4.18066 2.59112
H 4.12551 2.61952 2.99152
H 2.32886 0.64722 3.23285
H 0.80152 0.19671 3.70476
H 2.23703 0.20924 4.75333
C 3.98692 3.19145 4.36561
H 4.96530 2.79737 4.06074
H 3.81279 2.87185 5.39740
H 3.99778 4.28856 4.37035
O 1.75905 1.51930 0.84503
H 1.36853 2.29218 1.28841
H 0.99887 0.22346 2.22515
end
basis small
* library 321G
end
basis large
* library 631+G*
end
set "ao basis" small
cosmo
dielec 2.24
end
dft
xc b3lyp
CONVERGENCE density 1e8
CONVERGENCE energy 1e8
GRID lebedev 90 14 ssf euler
MAXITER 60
end
driver
EPREC 1e8
GRMS 0.000004
MAXITER 900
XYZ geomSteps_r2
end
task dft optimize
I really hope that i'm missing something. Thank you very much for help.




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4:08:14 AM PST  Fri, Feb 26th 2016 

i forgot to mention, that i checked results obtained on two different clusters, version 6.6 on both of them, but compiled independently on each other, by different person, with delay of ~6 months.




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11:59:05 AM PST  Fri, Feb 26th 2016 

The confusion is due to the solutesolvent interaction energy not being written explicitly in the output, i.e. the total energy is correct, you are just missing an energy component in the output.
The patch is available at
www.nwchemsw.org/download.php?f=Cosmo_dftprint.patch.gz




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12:28:31 PM PST  Fri, Feb 26th 2016 

that patch is new, right? also, i'm not sure, but in the COSMO part of the output i didn't attach originally is:
Total DFT energy = 1144.144378448133
One electron energy = 5654.477100400897
Coulomb energy = 2607.095668751906
ExchangeCorr. energy = 156.929943044225
Nuclear repulsion energy = 2058.598637126281
Numeric. integr. density = 178.000323079243
Total iterative time = 76.1s
COSMO solvation results

gas phase energy = 1144.1300273697
sol phase energy = 1144.1443784481
(electrostatic) solvation energy = 0.0143510784 ( 9.01 kcal/mol)
DFT Final Molecular Orbital Analysis
So I would assume that solvation energy is the solutesolvent interaction energy that you mentioned, isn't it? If so, than this energy is much smaller  only 0.01 Hartree, whereas the difference was bigger than 1 Hartree.
Of course, I'll apply the patch and try the calculation again.




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2:05:36 PM PST  Fri, Feb 26th 2016 

Yes, the patch is new, created this morning in response to your post.
The listed solvation energy is simply the difference in energy between the gas phase result and the solution phase result and not the solutesolvent interaction energy to which I was referring.



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