where's frequency of temperature fluctuation in OUTCAR?

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tjiang7
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where's frequency of temperature fluctuation in OUTCAR?

#1 Post by tjiang7 » Wed Mar 24, 2010 10:29 pm

Can anyone tell where is exactly the frequency of temperature fluctuation induced by Nose thermostat in the OUTCAR?
in the manual:
http://cms.mpi.univie.ac.at/vasp/guide/node118.html
it says we can find it in OUTCAR, but I don't see any 'frequency' in OUTCAR... Thanks ahead of time for any help.
<span class='smallblacktext'>[ Edited ]</span>
Last edited by tjiang7 on Wed Mar 24, 2010 10:29 pm, edited 1 time in total.

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where's frequency of temperature fluctuation in OUTCAR?

#2 Post by admin » Thu Mar 25, 2010 11:09 am

please search for the string
estimated Nose-frequenzy (Omega)
quite at the beginning of OUTCAR in the section summarizing the input parameters set for the Ionic relaxation
(in both vasp versions, 4.6 and 5.2)
Last edited by admin on Thu Mar 25, 2010 11:09 am, edited 1 time in total.

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where's frequency of temperature fluctuation in OUTCAR?

#3 Post by tjiang7 » Fri Mar 26, 2010 2:14 am

Thank you! one more question, so in OUTCAR it writes:
#####
estimated Nose-frequenzy (Omega) = 0.16E+15 period in steps = 40.00 mass= 0.191E-27a.u.
#####
my time step is 1fs, does that mean 0.16E+15 period in 40*1fs? How to calculate frequency?
Last edited by tjiang7 on Fri Mar 26, 2010 2:14 am, edited 1 time in total.

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where's frequency of temperature fluctuation in OUTCAR?

#4 Post by hess8 » Thu Mar 08, 2012 6:12 pm

That means your period is 40 fs, which gives an angular frequency (omega) of 0.16E15 rad/sec
Last edited by hess8 on Thu Mar 08, 2012 6:12 pm, edited 1 time in total.
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where's frequency of temperature fluctuation in OUTCAR?

#5 Post by admin » Fri Mar 09, 2012 1:46 pm

The Nose frequency in OUTCAR is in Hz. Another useful units are cm-1. Recalculate according to formula in
http://cms.mpi.univie.ac.at/vasp-forum/ ... hp?4.10860
0.16E+15 Hz = ~850 cm-1
Last edited by admin on Fri Mar 09, 2012 1:46 pm, edited 1 time in total.

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