MD Equilibration Issue – Temperature Fluctuations in CP2K
Hasan Tunçer
Hello,
I am running a molecular dynamics simulation using CP2K, and I am encountering difficulties in achieving equilibration. The temperature fluctuations remain significant, indicating that my system has not yet reached a stable state.
I have attached my CP2K input file for reference.
I would appreciate any insights or suggestions on how to stabilize the temperature and ensure proper equilibration. Thank you in advance for your time and assistance!
Best regards,
Hasan
Jürg Hutter
fluctuations in Temperature will be proportional to 1/SQRT(Natoms) and also
depending on you thermostat settings. I guess you are showing us a temperature
trajectory of a rather small molecule?
regards
JH
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Sent: Monday, February 3, 2025 5:06 PM
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Subject: [CP2K:21103] MD Equilibration Issue – Temperature Fluctuations in CP2K
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Thomas Kühne
let me add that by default REGION GLOBAL, i.e. only 1 or 3 degrees of freedom (DOFs) of the total system
are coupled to the thermostat. Please use REGION MASSIVE in which case 3 DOFs per atom are coupled
leading to much fast equipartition.
Best,
Thomas Kühne
> To view this discussion visit https://groups.google.com/d/msgid/cp2k/ZR0P278MB07599B5E6D8ACF4650A07F439FF42%40ZR0P278MB0759.CHEP278.PROD.OUTLOOK.COM.
> <temperature.png>
Hasan Tunçer
Thank you for your response! I appreciate the suggestion and will give it a try.
Regards,
Hasan
Hasan Tunçer
Thank you for your response. Yes, the data corresponds to a temperature trajectory of a 76-atom system. The thermostat settings are included in the input file attached to my previous email, but I am unsure if they are appropriately configured.
I would appreciate your feedback on whether any adjustments are needed.
Best regards,
Hasan
Hasan Tunçer
Dear Hasan Tuncer,