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| .. | ||
| .gitignore | ||
| fock_matrix_ks.irp.f | ||
| ks_enery.irp.f | ||
| ks_scf.irp.f | ||
| NEED | ||
| pot_functionals.irp.f | ||
| README.rst | ||
========= kohn_sham ========= The Kohn-Sham module performs *Restricted* Kohn-Sham calculations (the spatial part of the |MOs| is common for alpha and beta spinorbitals). The Kohn-Sham in an SCF and therefore is based on the ``scf_utils`` structure. It performs the following actions: #. Compute/Read all the one- and two-electron integrals, and store them in memory #. Check in the |EZFIO| database if there is a set of |MOs|. If there is, it will read them as initial guess. Otherwise, it will create a guess. #. Perform the |SCF| iterations The definition of the Fock matrix is in :file:`kohn_sham fock_matrix_ks.irp.f` For the keywords related to the |SCF| procedure, see the ``scf_utils`` directory where you will find all options. The main are: #. :option:`scf_utils thresh_scf` #. :option:`scf_utils level_shift` At each iteration, the |MOs| are saved in the |EZFIO| database. Hence, if the calculation crashes for any unexpected reason, the calculation can be restarted by running again the |SCF| with the same |EZFIO| database. The `DIIS`_ algorithm is implemented, as well as the `level-shifting`_ method. If the |SCF| does not converge, try again with a higher value of :option:`level_shift`. To start a calculation from scratch, the simplest way is to remove the ``mo_basis`` directory from the |EZFIO| database, and run the |SCF| again. .. _DIIS: https://en.wikipedia.org/w/index.php?title=DIIS .. _level-shifting: https://doi.org/10.1002/qua.560070407