.. _module_kohn_sham_rs: .. program:: kohn_sham_rs .. default-role:: option ============ kohn_sham_rs ============ The Range-separated Kohn-Sham module performs *Restricted* Kohn-Sham calculations (the spatial part of the |MOs| is common for alpha and beta spinorbitals) where the coulomb interaction is partially treated using exact exchange. The splitting of the interaction between long- and short-range is determined by the range-separation parameter :option:`ao_two_e_erf_ints mu_erf`. The long-range part of the interaction is explicitly treated with exact exchange, and the short-range part of the interaction is treated with appropriate DFT functionals. The Range-separated 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_rs fock_matrix_rs_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 EZFIO parameters ---------------- .. option:: energy Energy range separated hybrid Programs -------- * :ref:`rs_ks_scf` Providers --------- .. c:var:: ao_potential_alpha_xc File : :file:`pot_functionals.irp.f` .. code:: fortran double precision, allocatable :: ao_potential_alpha_xc (ao_num,ao_num) double precision, allocatable :: ao_potential_beta_xc (ao_num,ao_num) Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`potential_x_alpha_ao` Needed by: .. hlist:: :columns: 3 * :c:data:`fock_matrix_ao_alpha` * :c:data:`rs_ks_energy` .. c:var:: ao_potential_beta_xc File : :file:`pot_functionals.irp.f` .. code:: fortran double precision, allocatable :: ao_potential_alpha_xc (ao_num,ao_num) double precision, allocatable :: ao_potential_beta_xc (ao_num,ao_num) Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`potential_x_alpha_ao` Needed by: .. hlist:: :columns: 3 * :c:data:`fock_matrix_ao_alpha` * :c:data:`rs_ks_energy` .. c:var:: e_correlation_dft File : :file:`pot_functionals.irp.f` .. code:: fortran double precision :: e_correlation_dft Needs: .. hlist:: :columns: 3 * :c:data:`energy_x` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` * :c:data:`rs_ks_energy` .. c:var:: e_exchange_dft File : :file:`pot_functionals.irp.f` .. code:: fortran double precision :: e_exchange_dft Needs: .. hlist:: :columns: 3 * :c:data:`energy_x` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` * :c:data:`rs_ks_energy` .. c:var:: fock_matrix_alpha_no_xc_ao File : :file:`fock_matrix_rs_ks.irp.f` .. code:: fortran double precision, allocatable :: fock_matrix_alpha_no_xc_ao (ao_num,ao_num) double precision, allocatable :: fock_matrix_beta_no_xc_ao (ao_num,ao_num) Mono electronic an Coulomb matrix in AO basis set Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_two_e_integral_alpha` Needed by: .. hlist:: :columns: 3 * :c:data:`fock_matrix_ao_alpha` .. c:var:: fock_matrix_beta_no_xc_ao File : :file:`fock_matrix_rs_ks.irp.f` .. code:: fortran double precision, allocatable :: fock_matrix_alpha_no_xc_ao (ao_num,ao_num) double precision, allocatable :: fock_matrix_beta_no_xc_ao (ao_num,ao_num) Mono electronic an Coulomb matrix in AO basis set Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_two_e_integral_alpha` Needed by: .. hlist:: :columns: 3 * :c:data:`fock_matrix_ao_alpha` .. c:var:: fock_matrix_energy File : :file:`rs_ks_energy.irp.f` .. code:: fortran double precision :: rs_ks_energy double precision :: two_e_energy double precision :: one_e_energy double precision :: fock_matrix_energy double precision :: trace_potential_xc Range-separated Kohn-Sham energy containing the nuclear repulsion energy, and the various components of this quantity. Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_potential_alpha_xc` * :c:data:`ao_two_e_integral_alpha` * :c:data:`e_correlation_dft` * :c:data:`e_exchange_dft` * :c:data:`fock_matrix_ao_alpha` * :c:data:`nuclear_repulsion` * :c:data:`scf_density_matrix_ao_alpha` * :c:data:`scf_density_matrix_ao_beta` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` .. c:var:: one_e_energy File : :file:`rs_ks_energy.irp.f` .. code:: fortran double precision :: rs_ks_energy double precision :: two_e_energy double precision :: one_e_energy double precision :: fock_matrix_energy double precision :: trace_potential_xc Range-separated Kohn-Sham energy containing the nuclear repulsion energy, and the various components of this quantity. Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_potential_alpha_xc` * :c:data:`ao_two_e_integral_alpha` * :c:data:`e_correlation_dft` * :c:data:`e_exchange_dft` * :c:data:`fock_matrix_ao_alpha` * :c:data:`nuclear_repulsion` * :c:data:`scf_density_matrix_ao_alpha` * :c:data:`scf_density_matrix_ao_beta` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` .. c:var:: rs_ks_energy File : :file:`rs_ks_energy.irp.f` .. code:: fortran double precision :: rs_ks_energy double precision :: two_e_energy double precision :: one_e_energy double precision :: fock_matrix_energy double precision :: trace_potential_xc Range-separated Kohn-Sham energy containing the nuclear repulsion energy, and the various components of this quantity. Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_potential_alpha_xc` * :c:data:`ao_two_e_integral_alpha` * :c:data:`e_correlation_dft` * :c:data:`e_exchange_dft` * :c:data:`fock_matrix_ao_alpha` * :c:data:`nuclear_repulsion` * :c:data:`scf_density_matrix_ao_alpha` * :c:data:`scf_density_matrix_ao_beta` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` .. c:var:: trace_potential_xc File : :file:`rs_ks_energy.irp.f` .. code:: fortran double precision :: rs_ks_energy double precision :: two_e_energy double precision :: one_e_energy double precision :: fock_matrix_energy double precision :: trace_potential_xc Range-separated Kohn-Sham energy containing the nuclear repulsion energy, and the various components of this quantity. Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_potential_alpha_xc` * :c:data:`ao_two_e_integral_alpha` * :c:data:`e_correlation_dft` * :c:data:`e_exchange_dft` * :c:data:`fock_matrix_ao_alpha` * :c:data:`nuclear_repulsion` * :c:data:`scf_density_matrix_ao_alpha` * :c:data:`scf_density_matrix_ao_beta` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` .. c:var:: two_e_energy File : :file:`rs_ks_energy.irp.f` .. code:: fortran double precision :: rs_ks_energy double precision :: two_e_energy double precision :: one_e_energy double precision :: fock_matrix_energy double precision :: trace_potential_xc Range-separated Kohn-Sham energy containing the nuclear repulsion energy, and the various components of this quantity. Needs: .. hlist:: :columns: 3 * :c:data:`ao_num` * :c:data:`ao_one_e_integrals` * :c:data:`ao_potential_alpha_xc` * :c:data:`ao_two_e_integral_alpha` * :c:data:`e_correlation_dft` * :c:data:`e_exchange_dft` * :c:data:`fock_matrix_ao_alpha` * :c:data:`nuclear_repulsion` * :c:data:`scf_density_matrix_ao_alpha` * :c:data:`scf_density_matrix_ao_beta` Needed by: .. hlist:: :columns: 3 * :c:data:`extra_e_contrib_density` Subroutines / functions ----------------------- .. c:function:: check_coherence_functional: File : :file:`rs_ks_scf.irp.f` Needs: .. hlist:: :columns: 3 * :c:data:`exchange_functional` * :c:data:`correlation_functional` Called by: .. hlist:: :columns: 3 * :c:func:`rs_ks_scf`