[CP2K-user] [CP2K:20504] Re: Extremely High Temperature and Pressure Increase using NPT

[Michela Benazzi]

Hi Frederick, thank you very much for sharing this!

The spike occurs as soon as the simulation starts, hence why I shared the 
first couple frames. Would you still like me to include more?

- CP2K is not printing any warnings.
- Do you have any suggestions on what to look for when checking for 
accuracy? I have changed CUTOFF in the past.
- I could probably afford a larger basis set. The current one I am using 
was the same used in prior research in my lab, where admittedly they did 
not do much benchmarking! I can read more about zeta quality.
- I will also fix smearing. 

Sincerely thank you so much!! This gave me a good starting point and 
different opinions. Best,

Michela

On Friday, July 26, 2024 at 10:43:53 AM UTC-4 Frederick Stein wrote:

> Dear Michela,
> Your output is not really helpful to me, it would be better to have a few 
> frames around the spike. Does CP2K print any warnings? Spikes within MDs 
> may hint to too inaccurate setups (or just bad luck). My suggestions are:
> - did you check the accuracy of your setup (especially CUTOFF, EPS_DEFAULT)
> - are you sure that a single zeta basis set provides a sufficient accuracy 
> or can't you afford a larger basis set? For PBE, one should employ a basis 
> set of at least double-zeta, maybe even triple-zeta quality.
> - if you are already using smearing, you could use the actual temperature 
> as the electronic temperature (seems more physical to me)
> For more advanced suggestions, people more experienced in MD are open to 
> jump in.
> Best,
> Frederick
>
> Michela Benazzi schrieb am Freitag, 26. Juli 2024 um 16:18:24 UTC+2:
>
>> Hello, Can anyone please give me their opinion/advice? I am trying to run 
>> with TIMECON 50 (it was 1000 before), but no improvements yet.
>>
>> On Tuesday, July 23, 2024 at 7:23:56 AM UTC-4 Michela Benazzi wrote:
>>
>>> Hello everyone,
>>>
>>> I am running DFT at 1200 K, 1 bar with a periodic system of 64 Al atoms 
>>> + 2 CO2 atoms. However, I am seeing my temperature slowly increase to >4000 
>>> K and my pressure immediately spiking to ca. 2*10^5 bar.
>>>
>>> I was wondering if you could help me diagnose this issue - I thought 
>>> perhaps it was because I was not accounting for vdW interactions, but I 
>>> just added that term to my newer simulations and I am still incurring in 
>>> the same problem!
>>>
>>> I included below my input and shortened output.
>>>
>>>

-- 
You received this message because you are subscribed to the Google Groups "cp2k" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cp2k+unsubscribe at googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cp2k/8c2d7967-c051-4157-a531-b9bdfb83ff27n%40googlegroups.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20240726/efeb2b44/attachment.htm>