.. _module_cisd: .. program:: cisd .. default-role:: option ==== cisd ==== This module contains a CI of single and double excitations. The user point of view ---------------------- The :command:`cisd` program performs the CI of the ROHF-like + all single and double excitations on top of it. This program can be very useful to : * **Ground state calculations**: generate a guess for the ground state wave function if one is not sure that the :c:func:`scf` program gave the lowest SCF solution. In combination with :c:func:`save_natorb` it can produce new |MOs| in order to reperform an :c:func:`scf` optimization. * **Excited states calculations**: generate guess for all the :option:`determinants n_states` wave functions, that will be used by the :c:func:`fci` program. The main keywords/options to be used are: * :option:`determinants n_states` : number of states to consider for the |cisd| calculation * :option:`determinants s2_eig` : force all states to have the desired value of :math:`S^2` * :option:`determinants expected_s2` : desired value of :math:`S^2` The programmer point of view ---------------------------- This module have been built by setting the following rules: * The only generator determinant is the Hartree-Fock (single-reference method) * All generated determinants are included in the wave function (no perturbative selection) These rules are set in the ``H_apply.irp.f`` file. EZFIO parameters ---------------- .. option:: energy Variational |CISD| energy .. option:: lcc_energy lccsd energy Programs -------- * :ref:`cisd` * :ref:`lccsd` Providers --------- .. c:var:: lccsd_coef File : :file:`lccsd_prov.irp.f` .. code:: fortran double precision, allocatable :: lccsd_coef (N_det,N_states) double precision, allocatable :: lccsd_energies (N_states) Needs: .. hlist:: :columns: 3 * :c:data:`big_array_coulomb_integrals` * :c:data:`big_array_coulomb_integrals` * :c:data:`davidson_sze_max` * :c:data:`disk_based_davidson` * :c:data:`mo_integrals_map` * :c:data:`mo_two_e_integrals_in_map` * :c:data:`n_det` * :c:data:`n_int` * :c:data:`n_states` * :c:data:`n_states_diag` * :c:data:`nproc` * :c:data:`nthreads_davidson` * :c:data:`psi_det` * :c:data:`qp_max_mem` * :c:data:`ref_bitmask` * :c:data:`state_following` * :c:data:`threshold_davidson` .. c:var:: lccsd_energies File : :file:`lccsd_prov.irp.f` .. code:: fortran double precision, allocatable :: lccsd_coef (N_det,N_states) double precision, allocatable :: lccsd_energies (N_states) Needs: .. hlist:: :columns: 3 * :c:data:`big_array_coulomb_integrals` * :c:data:`big_array_coulomb_integrals` * :c:data:`davidson_sze_max` * :c:data:`disk_based_davidson` * :c:data:`mo_integrals_map` * :c:data:`mo_two_e_integrals_in_map` * :c:data:`n_det` * :c:data:`n_int` * :c:data:`n_states` * :c:data:`n_states_diag` * :c:data:`nproc` * :c:data:`nthreads_davidson` * :c:data:`psi_det` * :c:data:`qp_max_mem` * :c:data:`ref_bitmask` * :c:data:`state_following` * :c:data:`threshold_davidson` Subroutines / functions ----------------------- .. c:function:: get_lccsd_2: File : :file:`lccsd.irp.f` .. code:: fortran subroutine get_lccsd_2 Needs: .. hlist:: :columns: 3 * :c:data:`ha_to_ev` * :c:data:`lccsd_coef` * :c:data:`n_det` * :c:data:`n_states` * :c:data:`psi_coef` * :c:data:`save_threshold` Called by: .. hlist:: :columns: 3 * :c:func:`run` Calls: .. hlist:: :columns: 3 * :c:func:`ezfio_set_cisd_lcc_energy` * :c:func:`save_wavefunction_truncated` Touches: .. hlist:: :columns: 3 * :c:data:`psi_coef` .. c:function:: h_apply_cisd: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd() Calls H_apply on the |HF| determinant and selects all connected single and double excitations (of the same symmetry). Auto-generated by the ``generate_h_apply`` script. Needs: .. hlist:: :columns: 3 * :c:data:`generators_bitmask` * :c:data:`h_apply_buffer_allocated` * :c:data:`mo_num` * :c:data:`mo_two_e_integrals_in_map` * :c:data:`n_det` * :c:data:`n_det_generators` * :c:data:`n_int` * :c:data:`n_states` * :c:data:`psi_coef` * :c:data:`psi_det_generators` * :c:data:`psi_det` * :c:data:`psi_det_generators` * :c:data:`s2_eig` Called by: .. hlist:: :columns: 3 * :c:func:`run` * :c:func:`run_cisd` Calls: .. hlist:: :columns: 3 * :c:func:`build_fock_tmp` * :c:func:`copy_h_apply_buffer_to_wf` * :c:func:`dsort` * :c:func:`h_apply_cisd_diexc` * :c:func:`h_apply_cisd_monoexc` * :c:func:`make_s2_eigenfunction` * :c:func:`wall_time` Touches: .. hlist:: :columns: 3 * :c:data:`psi_configuration` * :c:data:`n_det` * :c:data:`c0_weight` * :c:data:`psi_coef` * :c:data:`psi_det_sorted_bit` * :c:data:`psi_configuration` * :c:data:`psi_det` * :c:data:`psi_det_size` * :c:data:`psi_det_sorted_bit` .. c:function:: h_apply_cisd_diexc: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_diexc(key_in, key_prev, hole_1,particl_1, hole_2, particl_2, fock_diag_tmp, i_generator, iproc_in ) Needs: .. hlist:: :columns: 3 * :c:data:`mo_num` * :c:data:`n_det` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd` Calls: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_diexcp` .. c:function:: h_apply_cisd_diexcorg: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_diexcOrg(key_in,key_mask,hole_1,particl_1,hole_2, particl_2, fock_diag_tmp, i_generator, iproc_in ) Generate all double excitations of key_in using the bit masks of holes and particles. Assume N_int is already provided. Needs: .. hlist:: :columns: 3 * :c:data:`elec_alpha_num` * :c:data:`mo_num` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_diexcp` Calls: .. hlist:: :columns: 3 * :c:func:`bitstring_to_list_ab` * :c:func:`fill_h_apply_buffer_no_selection` .. c:function:: h_apply_cisd_diexcp: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_diexcP(key_in, fs1, fh1, particl_1, fs2, fh2, particl_2, fock_diag_tmp, i_generator, iproc_in ) Needs: .. hlist:: :columns: 3 * :c:data:`mo_num` * :c:data:`n_det` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_diexc` Calls: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_diexcorg` .. c:function:: h_apply_cisd_monoexc: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_monoexc(key_in, hole_1,particl_1,fock_diag_tmp,i_generator,iproc_in ) Generate all single excitations of key_in using the bit masks of holes and particles. Assume N_int is already provided. Needs: .. hlist:: :columns: 3 * :c:data:`elec_alpha_num` * :c:data:`mo_num` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd` Calls: .. hlist:: :columns: 3 * :c:func:`bitstring_to_list_ab` * :c:func:`fill_h_apply_buffer_no_selection` .. c:function:: h_apply_cisd_sym: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_sym() Calls H_apply on the |HF| determinant and selects all connected single and double excitations (of the same symmetry). Auto-generated by the ``generate_h_apply`` script. Needs: .. hlist:: :columns: 3 * :c:data:`generators_bitmask` * :c:data:`h_apply_buffer_allocated` * :c:data:`mo_num` * :c:data:`mo_two_e_integrals_in_map` * :c:data:`n_det` * :c:data:`n_det_generators` * :c:data:`n_int` * :c:data:`n_states` * :c:data:`psi_coef` * :c:data:`psi_det_generators` * :c:data:`psi_det` * :c:data:`psi_det_generators` * :c:data:`s2_eig` Called by: .. hlist:: :columns: 3 * :c:func:`run` * :c:func:`run_cisd` Calls: .. hlist:: :columns: 3 * :c:func:`build_fock_tmp` * :c:func:`copy_h_apply_buffer_to_wf` * :c:func:`dsort` * :c:func:`h_apply_cisd_sym_diexc` * :c:func:`h_apply_cisd_sym_monoexc` * :c:func:`make_s2_eigenfunction` * :c:func:`wall_time` Touches: .. hlist:: :columns: 3 * :c:data:`psi_configuration` * :c:data:`n_det` * :c:data:`c0_weight` * :c:data:`psi_coef` * :c:data:`psi_det_sorted_bit` * :c:data:`psi_configuration` * :c:data:`psi_det` * :c:data:`psi_det_size` * :c:data:`psi_det_sorted_bit` .. c:function:: h_apply_cisd_sym_diexc: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_sym_diexc(key_in, key_prev, hole_1,particl_1, hole_2, particl_2, fock_diag_tmp, i_generator, iproc_in ) Needs: .. hlist:: :columns: 3 * :c:data:`mo_num` * :c:data:`n_det` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_sym` Calls: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_sym_diexcp` .. c:function:: h_apply_cisd_sym_diexcorg: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_sym_diexcOrg(key_in,key_mask,hole_1,particl_1,hole_2, particl_2, fock_diag_tmp, i_generator, iproc_in ) Generate all double excitations of key_in using the bit masks of holes and particles. Assume N_int is already provided. Needs: .. hlist:: :columns: 3 * :c:data:`elec_alpha_num` * :c:data:`mo_num` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_sym_diexcp` Calls: .. hlist:: :columns: 3 * :c:func:`bitstring_to_list_ab` * :c:func:`connected_to_hf` * :c:func:`fill_h_apply_buffer_no_selection` .. c:function:: h_apply_cisd_sym_diexcp: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_sym_diexcP(key_in, fs1, fh1, particl_1, fs2, fh2, particl_2, fock_diag_tmp, i_generator, iproc_in ) Needs: .. hlist:: :columns: 3 * :c:data:`mo_num` * :c:data:`n_det` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_sym_diexc` Calls: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_sym_diexcorg` .. c:function:: h_apply_cisd_sym_monoexc: File : :file:`h_apply.irp.f_shell_12` .. code:: fortran subroutine H_apply_cisd_sym_monoexc(key_in, hole_1,particl_1,fock_diag_tmp,i_generator,iproc_in ) Generate all single excitations of key_in using the bit masks of holes and particles. Assume N_int is already provided. Needs: .. hlist:: :columns: 3 * :c:data:`elec_alpha_num` * :c:data:`mo_num` * :c:data:`n_int` Called by: .. hlist:: :columns: 3 * :c:func:`h_apply_cisd_sym` Calls: .. hlist:: :columns: 3 * :c:func:`bitstring_to_list_ab` * :c:func:`connected_to_hf` * :c:func:`fill_h_apply_buffer_no_selection` .. c:function:: run_cisd: File : :file:`cisd_routine.irp.f` .. code:: fortran subroutine run_cisd Needs: .. hlist:: :columns: 3 * :c:data:`ci_electronic_energy` * :c:data:`ci_energy` * :c:data:`n_det` * :c:data:`n_states` * :c:data:`pseudo_sym` * :c:data:`psi_coef` Calls: .. hlist:: :columns: 3 * :c:func:`ezfio_set_cisd_energy` * :c:func:`h_apply_cisd` * :c:func:`h_apply_cisd_sym` * :c:func:`save_wavefunction` Touches: .. hlist:: :columns: 3 * :c:data:`psi_configuration` * :c:data:`n_det` * :c:data:`c0_weight` * :c:data:`psi_coef` * :c:data:`psi_det_sorted_bit` * :c:data:`psi_configuration` * :c:data:`psi_det` * :c:data:`psi_det_size` * :c:data:`psi_det_sorted_bit`