Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

GRADIENT -- Illegal Value for the Total Potential Energy #14

Open
heman3333 opened this issue Jul 7, 2023 · 3 comments
Open

GRADIENT -- Illegal Value for the Total Potential Energy #14

heman3333 opened this issue Jul 7, 2023 · 3 comments

Comments

@heman3333
Copy link

So I am running the simulation in NVE ensemble. For few picoseconds the simulation is running fine but after that
it gives the warning " Warning, system moved too much since last neighbor list update, try lowering nlupdate VDW ", which
I am not able to understand. Further the simulation got terminated giving the error "GRADIENT -- Illegal Value for the Total Potential Energy". Currently I am stuck here.
I am using Tinker-HP v1.2.

@louislagardere
Copy link
Member

That means that there is some instability in the simulation that lead to some movements of atoms that are too large given the frequency of update of the neighbour lists. To circumvent that, you can try reducing the "nlupdate" parameter in the key file (nludapte x), default value is 20 (time steps) for a 2fs simulation. Of course this can also mean that there is a more fondamental issue in your simulation that leads to some instability.

@heman3333
Copy link
Author

In fact, I have ran the simulation using the same key file without any error for some aqueous salt solutions.
This time, I have taken a little bit higher concentration and I ended up with this error.
Thanks for the suggestions and I will check nlupdate parameter in my key file.

@heman3333
Copy link
Author

Further, The same simulation with the same key file, running fine on other cluster. But giving error on another cluster.
Does it also depend on the computer architecture too ?

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants