Green/WeakCoupling 1.0.0: Symmetry-adapted self-consistent many-body perturbation theory for molecules and solids
Description
We present version 1.0.0 of Green/WeakCoupling, an open-source program for fully self-consistent finite-temperature many-body perturbation theory. The principal update integrates space-group symmetry into the Hartree–Fock and GW kernels, including double-group transformations for two-component relativistic calculations. Reconstruction of matrices and integral intermediates from irreducible momentum meshes reduces redundant work and preserves the symmetry of the electronic state. Silicon benchmarks demonstrate reduced CPU execution times, while a black-phosphorus calculation shows improved self-consistency stability. Further changes include revised input interfaces and orbital transformations, additional regression tests, and fixes in numerical kernels and timing modules. The physical approximations and basic workflow of the original program are retained.