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.

Sign up for GitHub

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

Jump to bottom

ELC energies (and forces?) might be of by factor 2 #4786

Closed
schlaicha opened this issue Sep 5, 2023 · 1 comment · Fixed by #4785
Closed

ELC energies (and forces?) might be of by factor 2 #4786

schlaicha opened this issue Sep 5, 2023 · 1 comment · Fixed by #4785

Comments

@schlaicha
Copy link
Contributor

Working on the new ELC-IC tutorial (#4784) @Frieda95 and myself realized that there might be a factor 2 missing somewhere.
Looking through the test in testuite/python/elc.py I realized that there only the interaction of the charges with the walls and applied field is tested.

#4785 proposes to add a test on the Madelung energy: A cubic latttice unit cell is created between two grounded metal interfaces such that the image charge interactions are the same as in an infinite crystal lattice.

According to this, the energy obtained from ELC-IC is twice as large as expected...
@jonaslandsgesell
Copy link
Member

Is this potentially related? #3001 (comment) there it looked like a scaling factor as well

@reinaual reinaual mentioned this issue Dec 8, 2023
Merged
@kodiakhq kodiakhq bot closed this as completed in #4785 Dec 8, 2023
kodiakhq bot added a commit that referenced this issue Dec 8, 2023
@kodiakhq
add elc test on madelung energy (#4785)

Verified

This commit was created on GitHub.com and signed with GitHub’s verified signature. The key has expired.
GPG key ID: 4AEE18F83AFDEB23
Expired
Verified
Learn about vigilant mode
898b4cb 
Fixes #4786 

For neutral systems ELC-IC still seems to work perfectly fine.

Description of changes:
- Improve testing of ELC using the Madelung energy
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
No milestone
Development

Successfully merging a pull request may close this issue.

add elc test on madelung energy schlaicha/espresso
2 participants
@schlaicha @jonaslandsgesell