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

Make use of ERI redundancies #55

Open
awf opened this issue Aug 30, 2023 · 0 comments
Open

Make use of ERI redundancies #55

awf opened this issue Aug 30, 2023 · 0 comments
Labels

Comments

@awf
Copy link
Collaborator

awf commented Aug 30, 2023

The ERI tensor has numerous redundancies:

  1. permutation invariances: E_ijkl = E_jikl etc
  2. orthogonalities: E_ijkl = 0 for some combinations of (i,j) in some basis sets
  3. sparsity: E_ijkl \approx 0 when atoms (ijkl) are far from each other

The electron repulsion integrals are stored in ERI and most of the entries are zero. Furthermore, ERI satisfies an 8x symmetry:

  • E_ij.. = E_ji.. # E is a symmetric matrix of ...
  • E_..kl = E_..lk # ... symmetric matrices
  • E_[ij][kl] = E_[kl][ij] # .. and one more symmetry

This file computes the ERI einsum using a sparse matrix vector multiplication.

@awf awf added the epic label Aug 30, 2023
@awf awf changed the title Make use of ERI redundancies to save memory Make use of ERI redundancies Aug 30, 2023
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
Projects
None yet
Development

No branches or pull requests

1 participant