From NWChem
Viewed 1341 times, With a total of 2 Posts
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Clicked A Few Times
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Posts 23
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| 4:50:22 AM PDT - Fri, Mar 27th 2015 |
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I have done a RT-TDDFT calculation that was stopped before finishing. I restarted it and it resumed from the last saved checkpoint as expected (a few time steps before the last time step previously calculated). When i compared fragment charge and dipole moment of the recalculated time steps with those previously calculated, they were both different:
Total charge of the first fragment vs time
Initial calculation
...
839.80000 -7.079210205400E+001
840.00000 -7.079139863826E+001
840.20000 -7.079034211879E+001
840.40000 -7.078864903884E+001
840.60000 -7.078666342819E+001
840.80000 -7.078418324505E+001
841.00000 -7.078199092129E+001
Restarted calculation
839.80000 -7.079210205400E+001
840.00000 -7.079016993950E+001
840.20000 -7.078538055498E+001
840.40000 -7.077990397372E+001
840.60000 -7.077981413108E+001
840.80000 -7.077998404146E+001
841.00000 -7.078424785058E+001
...
Restarted calculation resumes at t=839.8a.u. and prints exactly the same charge as before, but at t=840a.u. and subsequent time steps the results differ.
1) Shouldn't i get identical results for a resumed calculation?
2) How exactly is the charge of each fragment calculated at each time step after propagation of the density matrix?
Thanks,
Andreas
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Edited On 5:29:10 AM PDT - Sat, Mar 28th 2015 by Extremis
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Niri Forum:Admin, Forum:Mod, NWChemDeveloper, bureaucrat, sysop
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Forum Regular
Threads 4
Posts 209
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| 7:24:51 AM PDT - Thu, Apr 2nd 2015 |
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Hi Andreas,
Can you send me your input file, if possible ?
Best,
-Niri
niri.govind@pnnl.gov
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Clicked A Few Times
Threads 9
Posts 23
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| 3:02:35 PM PDT - Mon, Apr 13th 2015 |
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I created a very simple example just for testing: a Hydrogen molecule with an extra electron:
title "H2- charge transfer"
start hydrogen
geometry "h1" units angstroms noautosym nocenter noautoz
H 0.50000000 0.00000000 0.00000000
end
geometry "h2" units angstroms noautosym nocenter noautoz
H -0.50000000 0.00000000 0.00000000
end
geometry "pair" units angstroms noautosym nocenter noautoz
H 0.50000000 0.00000000 0.00000000
H -0.50000000 0.00000000 0.00000000
end
BASIS spherical
* library 3-21G
END
basis "cd basis"
* library "Ahlrichs Coulomb Fitting"
end
dft
xc xbnl07 0.90 lyp 1.00 hfexch 1.00
cam 0.33 cam_alpha 0.0 cam_beta 1.0
odft
convergence density 1d-9
grid fine
end
charge -1
set geometry "h1"
dft
mult 1
vectors input atomic output "h1.movecs"
end
task dft energy
charge 0
set geometry "h2"
dft
mult 2
vectors input atomic output "h2.movecs"
end
task dft energy
charge -1
set geometry "pair"
dft
mult 2
vectors input fragment "h1.movecs" "h2.movecs" output "pair.movecs"
noscf
end
task dft energy
rt_tddft
tmax 100.0
dt 0.2
load vectors "pair.movecs"
nrestarts 5
nchecks 5
print *
end
task dft rt_tddft
I ran it and after a few seconds i killed the process. Then, i restarted it:
restart hydrogen
task dft rt_tddft
It restarts successfully from a previously saved checkpoint, but charge and dipole moment differ:
Charge
Initial calculation
...
24.80000 -1.233793018676E+000
25.00000 -1.210558601777E+000
25.20000 -1.187089822858E+000
25.40000 -1.163415661715E+000
25.60000 -1.139710545366E+000
...
Restarted calculation
24.80000 -1.233793018676E+000
25.00000 -1.203827553217E+000
25.20000 -1.174313380229E+000
25.40000 -1.145364966307E+000
25.60000 -1.117188085409E+000
...
Dipole moment
Initial calculation
...
24.80000 4.863805326097E-001 0.000000000000E+000 0.000000000000E+000
25.00000 5.223713323234E-001 0.000000000000E+000 0.000000000000E+000
25.20000 5.571993826795E-001 0.000000000000E+000 0.000000000000E+000
25.40000 5.906750452401E-001 0.000000000000E+000 0.000000000000E+000
25.60000 6.225185939873E-001 0.000000000000E+000 0.000000000000E+000
...
Restarted calculation
24.80000 4.863805326097E-001 0.000000000000E+000 0.000000000000E+000
25.00000 5.266073747121E-001 0.000000000000E+000 0.000000000000E+000
25.20000 5.650030551657E-001 0.000000000000E+000 0.000000000000E+000
25.40000 6.014069077519E-001 0.000000000000E+000 0.000000000000E+000
25.60000 6.356380363757E-001 0.000000000000E+000 0.000000000000E+000
...
The same behavior is observed if i let it finish the calculation and then restart it for another say 100a.u.
-Andreas
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