subroutine give_1h2p_new(matrix_1h2p) use bitmasks implicit none double precision , intent(inout) :: matrix_1h2p(N_det,N_det,*) integer :: i,v,r,a,b,c integer :: iorb, vorb, rorb, aorb, borb,corb integer :: ispin,jspin integer :: idet,jdet integer(bit_kind) :: perturb_dets(N_int,2,n_act_orb,2,2) double precision :: perturb_dets_phase(n_act_orb,2,2) double precision :: perturb_dets_hij(n_act_orb,2,2) double precision :: perturb_dets_hpsi0(n_act_orb,2,2,N_states) logical :: already_generated(n_act_orb,2,2) integer :: inint integer :: elec_num_tab_local(2),acu_elec integer(bit_kind) :: det_tmp(N_int,2) integer(bit_kind) :: det_tmp_j(N_int,2) integer :: exc(0:2,2,2) integer :: accu_elec double precision :: get_mo_bielec_integral double precision :: active_int(n_act_orb,2) double precision :: hij,phase double precision :: accu_contrib(N_states) integer :: degree(N_det) integer :: idx(0:N_det) double precision :: delta_e(n_act_orb,2,N_states) double precision :: delta_e_inv(n_act_orb,2,N_states) double precision :: delta_e_inactive_virt(N_states) integer :: istate integer :: index_orb_act_mono(N_det,6) integer :: kspin double precision :: delta_e_ja(N_states) double precision :: hja double precision :: contrib_hij double precision :: fock_operator_local(n_act_orb,n_act_orb,2) double precision :: hij_test integer ::i_ok integer(bit_kind) :: det_tmp_bis(N_int,2) double precision :: hib , hab double precision :: delta_e_ab(N_states) double precision :: hib_test,hja_test,hab_test integer :: i_hole,i_part double precision :: hia,hjb integer :: other_spin(2) other_spin(1) = 2 other_spin(2) = 1 accu_contrib = 0.d0 !matrix_1h2p = 0.d0 elec_num_tab_local = 0 do inint = 1, N_int elec_num_tab_local(1) += popcnt(psi_det(inint,1,1)) elec_num_tab_local(2) += popcnt(psi_det(inint,2,1)) enddo do i = 1, n_inact_orb ! First inactive iorb = list_inact(i) do v = 1, n_virt_orb ! First virtual vorb = list_virt(v) do r = 1, n_virt_orb ! Second virtual rorb = list_virt(r) ! take all the integral you will need for i,j,r fixed do a = 1, n_act_orb aorb = list_act(a) active_int(a,1) = get_mo_bielec_integral(iorb,aorb,rorb,vorb,mo_integrals_map) ! direct active_int(a,2) = get_mo_bielec_integral(iorb,aorb,vorb,rorb,mo_integrals_map) ! exchange perturb_dets_phase(a,1,1) = -1000.d0 perturb_dets_phase(a,1,2) = -1000.d0 perturb_dets_phase(a,2,2) = -1000.d0 perturb_dets_phase(a,2,1) = -1000.d0 enddo do istate = 1, N_states delta_e_inactive_virt(istate) = & - fock_virt_total_spin_trace(rorb,istate) & - fock_virt_total_spin_trace(vorb,istate) & + fock_core_inactive_total_spin_trace(iorb,istate) enddo do idet = 1, N_det call get_excitation_degree_vector_mono_or_exchange(psi_det,psi_det(1,1,idet),degree,N_int,N_det,idx) !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Precomputation of matrix elements do ispin = 1, 2 ! spin of the couple a-a^dagger (iorb,rorb) do jspin = 1, 2 ! spin of the couple a-a^dagger (aorb,vorb) do a = 1, n_act_orb ! First active aorb = list_act(a) do istate = 1, N_states perturb_dets_hpsi0(a,jspin,ispin,istate) = 0.d0 enddo if(ispin == jspin .and. vorb.le.rorb)cycle ! condition not to double count do inint = 1, N_int det_tmp(inint,1) = psi_det(inint,1,idet) det_tmp(inint,2) = psi_det(inint,2,idet) enddo ! Do the excitation inactive -- > virtual call clear_bit_to_integer(iorb,det_tmp(1,ispin),N_int) ! hole in "iorb" of spin Ispin call set_bit_to_integer(rorb,det_tmp(1,ispin),N_int) ! particle in "rorb" of spin Ispin ! Do the excitation active -- > virtual call clear_bit_to_integer(aorb,det_tmp(1,jspin),N_int) ! hole in "aorb" of spin Jspin call set_bit_to_integer(vorb,det_tmp(1,jspin),N_int) ! particle in "vorb" of spin Jspin ! Check if the excitation is possible or not on psi_det(idet) accu_elec= 0 do inint = 1, N_int accu_elec+= popcnt(det_tmp(inint,jspin)) enddo if(accu_elec .ne. elec_num_tab_local(jspin))then perturb_dets_phase(a,jspin,ispin) = -1000.0d0 perturb_dets_hij(a,jspin,ispin) = 0.d0 cycle endif do inint = 1, N_int perturb_dets(inint,1,a,jspin,ispin) = det_tmp(inint,1) perturb_dets(inint,2,a,jspin,ispin) = det_tmp(inint,2) enddo call get_double_excitation(psi_det(1,1,idet),det_tmp,exc,phase,N_int) perturb_dets_phase(a,jspin,ispin) = phase do istate = 1, N_states delta_e(a,jspin,istate) = one_anhil(a,jspin,istate) + delta_e_inactive_virt(istate) delta_e_inv(a,jspin,istate) = 1.d0 / delta_e(a,jspin,istate) enddo if(ispin == jspin)then perturb_dets_hij(a,jspin,ispin) = phase * (active_int(a,1) - active_int(a,2) ) else perturb_dets_hij(a,jspin,ispin) = phase * active_int(a,1) endif enddo enddo enddo !!!!!!!!!!!!!!!!!!!!!!!!!!! determination of the connections between I and the other J determinants mono excited in the CAS !!!!!!!!!!!!!!!!!!!!!!!!!!!! the determinants I and J must be connected by the following operator !!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!! do jdet = 1, idx(0) if(degree(jdet)==1)then call get_mono_excitation(psi_det(1,1,idet),psi_det(1,1,idx(jdet)),exc,phase,N_int) if (exc(0,1,1) == 1) then ! Mono alpha i_hole = list_act_reverse(exc(1,1,1)) !!! a_a i_part = list_act_reverse(exc(1,2,1)) !!! a^{\dagger}_{b} kspin = 1 !!! kspin index_orb_act_mono(idx(jdet),1) = i_hole index_orb_act_mono(idx(jdet),2) = i_part index_orb_act_mono(idx(jdet),3) = kspin call i_H_j_dyall(psi_active(1,1,idet),psi_active(1,1,idx(jdet)),N_int,hij) fock_operator_local(i_hole,i_part,kspin) = hij * phase ! phase less fock operator fock_operator_local(i_part,i_hole,kspin) = hij * phase ! phase less fock operator else ! Mono beta i_hole = list_act_reverse(exc(1,1,2)) !!! a_a i_part = list_act_reverse(exc(1,2,2)) !!! a^{\dagger}_{b} kspin = 2 !!! kspin index_orb_act_mono(idx(jdet),1) = i_hole index_orb_act_mono(idx(jdet),2) = i_part index_orb_act_mono(idx(jdet),3) = kspin call i_H_j_dyall(psi_active(1,1,idet),psi_active(1,1,idx(jdet)),N_int,hij) fock_operator_local(i_hole,i_part,kspin) = hij * phase ! phase less fock operator fock_operator_local(i_part,i_hole,kspin) = hij * phase ! phase less fock operator endif else if(degree(jdet)==2)then call get_double_excitation(psi_det(1,1,idet),psi_det(1,1,idx(jdet)),exc,phase,N_int) ! Mono alpha index_orb_act_mono(idx(jdet),1) = list_act_reverse(exc(1,1,1)) !!! a_a ALPHA index_orb_act_mono(idx(jdet),2) = list_act_reverse(exc(1,2,1)) !!! a^{\dagger}_{b} ALPHA index_orb_act_mono(idx(jdet),3) = 1 ! Mono beta index_orb_act_mono(idx(jdet),4) = list_act_reverse(exc(1,1,2)) !!! a_a BETA index_orb_act_mono(idx(jdet),5) = list_act_reverse(exc(1,2,2)) !!! a^{\dagger}_{b} BETA index_orb_act_mono(idx(jdet),6) = 2 endif enddo do jdet = 1, idx(0) !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! CASE OF THE MONO EXCITATIONS if(degree(jdet) == 1)then ! two determinants | Idet > and | Jdet > which are connected throw a mono excitation operator ! are connected by the presence of the perturbers determinants |det_tmp> aorb = index_orb_act_mono(idx(jdet),1) ! a_{aorb} borb = index_orb_act_mono(idx(jdet),2) ! a^{\dagger}_{borb} kspin = index_orb_act_mono(idx(jdet),3) ! spin of the excitation ! the determinants Idet and Jdet interact throw the following operator ! | Jdet > = a^{\dagger}_{borb,kspin} a_{aorb, kspin} | Idet > accu_contrib = 0.d0 do ispin = 1, 2 ! you loop on all possible spin for the excitation ! a^{\dagger}_r a_{i} (ispin) ! if(ispin == kspin .and. vorb.le.rorb)cycle ! condition not to double count logical :: cycle_same_spin_first_order cycle_same_spin_first_order = .False. if(ispin == kspin .and. vorb.le.rorb)then cycle_same_spin_first_order = .True. endif ! if(ispin .ne. kspin .and. cycle_same_spin_first_order .eqv. .False. )then ! condition not to double count if(cycle_same_spin_first_order .eqv. .False. )then ! condition not to double count ! FIRST ORDER CONTRIBUTION ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{vorb,kspin} a_{aorb,kspin} a_{iorb,ispin} | Idet > if(perturb_dets_phase(aorb,kspin,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,aorb,kspin,ispin) det_tmp(inint,2) = perturb_dets(inint,2,aorb,kspin,ispin) enddo call get_double_excitation(psi_det(1,1,idet),det_tmp,exc,phase,N_int) if(kspin == ispin)then hia = phase * (active_int(aorb,1) - active_int(aorb,2) ) else hia = phase * active_int(aorb,1) endif call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp,exc,phase,N_int) if(kspin == ispin)then hja = phase * (active_int(borb,1) - active_int(borb,2) ) else hja = phase * active_int(borb,1) endif contrib_hij = hja * hia do istate = 1, N_states accu_contrib(istate) += contrib_hij * delta_e_inv(aorb,kspin,istate) enddo endif !!!! SECOND ORDER CONTRIBTIONS ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{vorb,jspin} a_{corb,jspin} a_{iorb,ispin} | Idet > do jspin = 1, 2 logical :: cycle_same_spin_second_order cycle_same_spin_second_order = .False. if(ispin == jspin .and. vorb.le.rorb)then cycle_same_spin_second_order = .True. endif if(cycle_same_spin_second_order .eqv. .False.)then do corb = 1, n_act_orb if(perturb_dets_phase(corb,jspin,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,corb,jspin,ispin) det_tmp(inint,2) = perturb_dets(inint,2,corb,jspin,ispin) det_tmp_bis(inint,1) = perturb_dets(inint,1,corb,jspin,ispin) det_tmp_bis(inint,2) = perturb_dets(inint,2,corb,jspin,ispin) enddo ! | det_tmp_bis > = a^{\dagger}_{borb,kspin} a_{aorb,kspin} a_{iorb,ispin} | Idet > call do_mono_excitation(det_tmp_bis,list_act(aorb),list_act(borb),kspin,i_ok) if(i_ok .ne. 1)cycle call get_mono_excitation(det_tmp,det_tmp_bis,exc,phase,N_int) hia = perturb_dets_hij(corb,jspin,ispin) hab = fock_operator_local(aorb,borb,kspin) * phase if(dabs(hia).le.1.d-12)cycle if(dabs(hab).le.1.d-12)cycle call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp_bis,exc,phase,N_int) if(jspin == ispin)then hjb = phase * (active_int(corb,1) - active_int(corb,2) ) else hjb = phase * active_int(corb,1) endif if(dabs(hjb).le.1.d-12)cycle do istate = 1, N_states accu_contrib(istate)+=hia * delta_e_inv(corb,jspin,istate) & ! | Idet > --> | det_tmp > ! | det_tmp > --> | det_tmp_bis > *hab / (delta_e(corb,jspin,istate) + one_anhil_one_creat(aorb,borb,kspin,kspin,istate)) & *hjb enddo enddo endif enddo enddo ! ispin do istate = 1, N_states matrix_1h2p(idet,idx(jdet),istate) += accu_contrib(istate) enddo else if (degree(jdet) == 2)then ! CASE OF THE DOUBLE EXCITATIONS, ONLY THIRD ORDER EFFECTS accu_contrib = 0.d0 do ispin = 1, 2 ! you loop on all possible spin for the excitation ! a^{\dagger}_r a_{i} (ispin) ! if it is standard exchange case, the hole ALPHA == the part. BETA if (index_orb_act_mono(idx(jdet),1) == index_orb_act_mono(idx(jdet),5))then aorb = index_orb_act_mono(idx(jdet),1) !! the HOLE of the ALPHA electron borb = index_orb_act_mono(idx(jdet),4) !! the HOLE of the BETA electron ! first case :: | det_tmp > == a_{borb,\beta} | Idet > cycle_same_spin_second_order = .False. if(ispin == 2 .and. vorb.le.rorb)then cycle_same_spin_second_order = .True. endif if(cycle_same_spin_second_order .eqv. .False.)then ! condition not to double count if(perturb_dets_phase(borb,2,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,borb,2,ispin) det_tmp(inint,2) = perturb_dets(inint,2,borb,2,ispin) det_tmp_bis(inint,1) = perturb_dets(inint,1,borb,2,ispin) det_tmp_bis(inint,2) = perturb_dets(inint,2,borb,2,ispin) enddo hia = perturb_dets_hij(borb,2,ispin) if(dabs(hia).le.1.d-12)cycle call do_mono_excitation(det_tmp_bis,list_act(aorb),list_act(borb),1,i_ok) call get_mono_excitation(det_tmp,det_tmp_bis,exc,phase,N_int) hab = fock_operator_local(aorb,borb,1) * phase if(dabs(hab).le.1.d-12)cycle call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp_bis,exc,phase,N_int) if(ispin == 2)then hjb = phase * (active_int(aorb,1) - active_int(aorb,2) ) else if (ispin == 1)then hjb = phase * active_int(aorb,1) endif if(dabs(hjb).le.1.d-12)cycle do istate = 1, N_states accu_contrib(istate) += hia * delta_e_inv(borb,2,istate) & ! | Idet > --> | det_tmp > ! | det_tmp > --> | det_tmp_bis > * hab / (delta_e(borb,2,istate) + one_anhil_one_creat(aorb,borb,1,1,istate)) & * hjb enddo endif ! second case :: | det_tmp > == a_{aorb,\alpha} | Idet > cycle_same_spin_second_order = .False. if(ispin == 1 .and. vorb.le.rorb)then cycle_same_spin_second_order = .True. endif if(cycle_same_spin_second_order .eqv. .False.)then ! condition not to double count if(perturb_dets_phase(aorb,1,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,aorb,1,ispin) det_tmp(inint,2) = perturb_dets(inint,2,aorb,1,ispin) det_tmp_bis(inint,1) = perturb_dets(inint,1,aorb,1,ispin) det_tmp_bis(inint,2) = perturb_dets(inint,2,aorb,1,ispin) enddo hia = perturb_dets_hij(aorb,1,ispin) if(dabs(hia).le.1.d-12)cycle call do_mono_excitation(det_tmp_bis,list_act(borb),list_act(aorb),2,i_ok) call get_mono_excitation(det_tmp,det_tmp_bis,exc,phase,N_int) hab = fock_operator_local(aorb,borb,2) * phase if(dabs(hab).le.1.d-12)cycle call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp_bis,exc,phase,N_int) if(ispin == 1)then hjb = phase * (active_int(borb,1) - active_int(borb,2) ) else if (ispin == 2)then hjb = phase * active_int(borb,1) endif if(dabs(hjb).le.1.d-12)cycle do istate = 1, N_states accu_contrib(istate) += hia * delta_e_inv(aorb,1,istate) & ! | Idet > --> | det_tmp > ! | det_tmp > --> | det_tmp_bis > * hab / (delta_e(aorb,1,istate) + one_anhil_one_creat(borb,aorb,2,2,istate)) & * hjb enddo endif ! if it is a closed shell double excitation, the hole ALPHA == the hole BETA else if (index_orb_act_mono(idx(jdet),1) == index_orb_act_mono(idx(jdet),4))then aorb = index_orb_act_mono(idx(jdet),1) !! the HOLE of the ALPHA electron borb = index_orb_act_mono(idx(jdet),2) !! the PART of the ALPHA electron ! first case :: | det_tmp > == a_{aorb,\beta} | Idet > cycle_same_spin_second_order = .False. if(ispin == 2 .and. vorb.le.rorb)then cycle_same_spin_second_order = .True. endif if(cycle_same_spin_second_order .eqv. .False.)then ! condition not to double count if(perturb_dets_phase(aorb,2,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,aorb,2,ispin) det_tmp(inint,2) = perturb_dets(inint,2,aorb,2,ispin) det_tmp_bis(inint,1) = perturb_dets(inint,1,aorb,2,ispin) det_tmp_bis(inint,2) = perturb_dets(inint,2,aorb,2,ispin) enddo hia = perturb_dets_hij(aorb,2,ispin) if(dabs(hia).le.1.d-12)cycle call do_mono_excitation(det_tmp_bis,list_act(aorb),list_act(borb),1,i_ok) call get_mono_excitation(det_tmp,det_tmp_bis,exc,phase,N_int) hab = fock_operator_local(aorb,borb,1) * phase if(dabs(hab).le.1.d-12)cycle call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp_bis,exc,phase,N_int) if(ispin == 2)then hjb = phase * (active_int(borb,1) - active_int(borb,2) ) else if (ispin == 1)then hjb = phase * active_int(borb,1) endif if(dabs(hjb).le.1.d-12)cycle do istate = 1, N_states accu_contrib(istate) += hia * delta_e_inv(aorb,2,istate) & ! | Idet > --> | det_tmp > ! | det_tmp > --> | det_tmp_bis > * hab / (delta_e(aorb,2,istate) + one_anhil_one_creat(aorb,borb,1,1,istate)) & * hjb enddo endif ! second case :: | det_tmp > == a_{aorb,\alpha} | Idet > cycle_same_spin_second_order = .False. if(ispin == 1 .and. vorb.le.rorb)then cycle_same_spin_second_order = .True. endif if(cycle_same_spin_second_order .eqv. .False.)then ! condition not to double count if(perturb_dets_phase(aorb,1,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,aorb,1,ispin) det_tmp(inint,2) = perturb_dets(inint,2,aorb,1,ispin) det_tmp_bis(inint,1) = perturb_dets(inint,1,aorb,1,ispin) det_tmp_bis(inint,2) = perturb_dets(inint,2,aorb,1,ispin) enddo hia = perturb_dets_hij(aorb,1,ispin) if(dabs(hia).le.1.d-12)cycle call do_mono_excitation(det_tmp_bis,list_act(aorb),list_act(borb),2,i_ok) call get_mono_excitation(det_tmp,det_tmp_bis,exc,phase,N_int) hab = fock_operator_local(aorb,borb,2) * phase if(dabs(hab).le.1.d-12)cycle call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp_bis,exc,phase,N_int) if(ispin == 1)then hjb = phase * (active_int(borb,1) - active_int(borb,2) ) else if (ispin == 2)then hjb = phase * active_int(borb,1) endif if(dabs(hjb).le.1.d-12)cycle do istate = 1, N_states accu_contrib(istate) += hia * delta_e_inv(aorb,1,istate) & ! | Idet > --> | det_tmp > ! | det_tmp > --> | det_tmp_bis > * hab / (delta_e(aorb,1,istate) + one_anhil_one_creat(aorb,borb,2,2,istate)) & * hjb enddo endif else ! one should not fall in this case ... call debug_det(psi_det(1,1,i),N_int) call debug_det(psi_det(1,1,idx(jdet)),N_int) call get_double_excitation(psi_det(1,1,idet),psi_det(1,1,idx(jdet)),exc,phase,N_int) call decode_exc(exc,2,h1,p1,h2,p2,s1,s2) integer :: h1, p1, h2, p2, s1, s2 print*, h1, p1, h2, p2, s1, s2 print*, 'pb !!! it is a double but not an exchange case ....' stop endif enddo ! ispin do istate = 1, N_states matrix_1h2p(idet,idx(jdet),istate) += accu_contrib(istate) enddo else if (degree(jdet) == 0)then ! diagonal part of the dressing : interaction of | Idet > with all the perturbers generated by the excitations ! ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{vorb,kspin} a_{aorb,kspin} a_{iorb,ispin} | Idet > accu_contrib = 0.d0 do ispin = 1, 2 do kspin = 1, 2 do a = 1, n_act_orb ! First active if( perturb_dets_phase(a,kspin,ispin) .le. -10.d0)cycle if(ispin == kspin .and. vorb.le.rorb)cycle ! condition not to double count contrib_hij = perturb_dets_hij(a,kspin,ispin) * perturb_dets_hij(a,kspin,ispin) do istate = 1, N_states accu_contrib(istate) += contrib_hij * delta_e_inv(a,kspin,istate) enddo enddo enddo enddo do istate = 1, N_states matrix_1h2p(idet,idet,istate) += accu_contrib(istate) enddo endif enddo !! jdet enddo enddo enddo enddo end subroutine give_2h1p_new(matrix_2h1p) use bitmasks implicit none double precision , intent(inout) :: matrix_2h1p(N_det,N_det,*) integer :: i,j,r,a,b integer :: iorb, jorb, rorb, aorb, borb integer :: ispin,jspin integer :: idet,jdet integer(bit_kind) :: perturb_dets(N_int,2,n_act_orb,2,2) double precision :: perturb_dets_phase(n_act_orb,2,2) double precision :: perturb_dets_hij(n_act_orb,2,2) integer :: inint integer :: elec_num_tab_local(2),acu_elec integer(bit_kind) :: det_tmp(N_int,2) integer :: exc(0:2,2,2) integer :: accu_elec double precision :: get_mo_bielec_integral double precision :: active_int(n_act_orb,2) double precision :: hij,phase integer :: i_hole,i_part double precision :: delta_e_inv(n_act_orb,2,N_states) double precision :: fock_operator_local(n_act_orb,n_act_orb,2) double precision :: delta_e_inactive_virt(N_states) integer :: degree(N_det) integer :: idx(0:N_det) double precision :: delta_e(n_act_orb,2,N_states) integer :: istate integer :: index_orb_act_mono(N_det,3) integer :: kspin double precision :: hij_test double precision :: accu_contrib(N_states) double precision :: contrib_hij double precision :: hja integer :: corb,i_ok integer(bit_kind) :: det_tmp_bis(N_int,2) double precision :: hia,hjb,hab !matrix_2h1p = 0.d0 elec_num_tab_local = 0 do inint = 1, N_int elec_num_tab_local(1) += popcnt(psi_det(inint,1,1)) elec_num_tab_local(2) += popcnt(psi_det(inint,2,1)) enddo do i = 1, n_inact_orb ! First inactive iorb = list_inact(i) do j = 1, n_inact_orb ! Second inactive jorb = list_inact(j) do r = 1, n_virt_orb ! First virtual rorb = list_virt(r) ! take all the integral you will need for i,j,r fixed do a = 1, n_act_orb aorb = list_act(a) active_int(a,1) = get_mo_bielec_integral(iorb,jorb,rorb,aorb,mo_integrals_map) ! direct active_int(a,2) = get_mo_bielec_integral(iorb,jorb,aorb,rorb,mo_integrals_map) ! exchange perturb_dets_phase(a,1,1) = -1000.d0 perturb_dets_phase(a,1,2) = -1000.d0 perturb_dets_phase(a,2,2) = -1000.d0 perturb_dets_phase(a,2,1) = -1000.d0 enddo do istate = 1, N_states delta_e_inactive_virt(istate) = & - fock_virt_total_spin_trace(rorb,istate) & + fock_core_inactive_total_spin_trace(iorb,istate) & + fock_core_inactive_total_spin_trace(jorb,istate) enddo do idet = 1, N_det call get_excitation_degree_vector_mono(psi_det,psi_det(1,1,idet),degree,N_int,N_det,idx) !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Precomputation of matrix elements do ispin = 1, 2 ! spin of the couple a-a^dagger (i,r) do jspin = 1, 2 ! spin of the couple z-a^dagger (j,a) if(ispin == jspin .and. iorb.le.jorb)cycle ! condition not to double count do a = 1, n_act_orb ! First active aorb = list_act(a) do inint = 1, N_int det_tmp(inint,1) = psi_det(inint,1,idet) det_tmp(inint,2) = psi_det(inint,2,idet) enddo ! Do the excitation inactive -- > virtual call clear_bit_to_integer(iorb,det_tmp(1,ispin),N_int) ! hole in "iorb" of spin Ispin call set_bit_to_integer(rorb,det_tmp(1,ispin),N_int) ! particle in "rorb" of spin Ispin ! Do the excitation inactive -- > active call clear_bit_to_integer(jorb,det_tmp(1,jspin),N_int) ! hole in "jorb" of spin Jspin call set_bit_to_integer(aorb,det_tmp(1,jspin),N_int) ! particle in "aorb" of spin Jspin ! Check if the excitation is possible or not on psi_det(idet) accu_elec= 0 do inint = 1, N_int accu_elec+= popcnt(det_tmp(inint,jspin)) enddo if(accu_elec .ne. elec_num_tab_local(jspin))then perturb_dets_phase(a,jspin,ispin) = -1000.0d0 perturb_dets_hij(a,jspin,ispin) = 0.d0 cycle endif do inint = 1, N_int perturb_dets(inint,1,a,jspin,ispin) = det_tmp(inint,1) perturb_dets(inint,2,a,jspin,ispin) = det_tmp(inint,2) enddo call get_double_excitation(psi_det(1,1,idet),det_tmp,exc,phase,N_int) perturb_dets_phase(a,jspin,ispin) = phase do istate = 1, N_states delta_e(a,jspin,istate) = one_creat(a,jspin,istate) + delta_e_inactive_virt(istate) delta_e_inv(a,jspin,istate) = 1.d0 / delta_e(a,jspin,istate) enddo if(ispin == jspin)then perturb_dets_hij(a,jspin,ispin) = phase * (active_int(a,1) - active_int(a,2) ) else perturb_dets_hij(a,jspin,ispin) = phase * active_int(a,1) endif !!!!!!!!!!!!!!!!!!!!!1 Computation of the coefficient at first order coming from idet !!!!!!!!!!!!!!!!!!!!! for the excitation (i,j)(ispin,jspin) ---> (r,a)(ispin,jspin) enddo enddo enddo !!!!!!!!!!!!!!!!!!!!!!!!!!! determination of the connections between I and the other J determinants mono excited in the CAS !!!!!!!!!!!!!!!!!!!!!!!!!!!! the determinants I and J must be connected by the following operator !!!!!!!!!!!!!!!!!!!!!!!!!!!! do jdet = 1, idx(0) if(degree(jdet)==1)then call get_mono_excitation(psi_det(1,1,idet),psi_det(1,1,idx(jdet)),exc,phase,N_int) if (exc(0,1,1) == 1) then ! Mono alpha i_part = list_act_reverse(exc(1,2,1)) ! a^{\dagger}_{aorb} i_hole = list_act_reverse(exc(1,1,1)) ! a_{borb} kspin = 1 index_orb_act_mono(idx(jdet),1) = i_part !!! a^{\dagger}_a index_orb_act_mono(idx(jdet),2) = i_hole !!! a_{b} index_orb_act_mono(idx(jdet),3) = 1 call i_H_j_dyall(psi_active(1,1,idet),psi_active(1,1,idx(jdet)),N_int,hij) fock_operator_local(i_hole,i_part,kspin) = hij * phase ! phase less fock operator fock_operator_local(i_part,i_hole,kspin) = hij * phase ! phase less fock operator else ! Mono beta i_part = list_act_reverse(exc(1,2,2)) i_hole = list_act_reverse(exc(1,1,2)) kspin = 2 index_orb_act_mono(idx(jdet),1) = i_part !!! a^{\dagger}_a index_orb_act_mono(idx(jdet),2) = i_hole !!! a_{b} index_orb_act_mono(idx(jdet),3) = 2 call i_H_j_dyall(psi_active(1,1,idet),psi_active(1,1,idx(jdet)),N_int,hij) fock_operator_local(i_hole,i_part,kspin) = hij * phase ! phase less fock operator fock_operator_local(i_part,i_hole,kspin) = hij * phase ! phase less fock operator endif endif enddo do jdet = 1, idx(0) ! two determinants | Idet > and | Jdet > which are connected throw a mono excitation operator ! are connected by the presence of the perturbers determinants |det_tmp> if(degree(jdet) == 1)then aorb = index_orb_act_mono(idx(jdet),1) ! a^{\dagger}_{aorb} borb = index_orb_act_mono(idx(jdet),2) ! a_{borb} kspin = index_orb_act_mono(idx(jdet),3) ! spin of the excitation ! the determinants Idet and Jdet interact throw the following operator ! | Jdet > = a_{borb,kspin} a^{\dagger}_{aorb, kspin} | Idet > accu_contrib = 0.d0 do ispin = 1, 2 ! you loop on all possible spin for the excitation ! a^{\dagger}_r a_{i} (ispin) ! if(ispin == kspin .and. iorb.le.jorb)cycle ! condition not to double count logical :: cycle_same_spin_first_order cycle_same_spin_first_order = .False. if(ispin == kspin .and. iorb.le.jorb)then cycle_same_spin_first_order = .True. endif if(ispin .ne. kspin .or. cycle_same_spin_first_order .eqv. .False. )then! condition not to double count ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{aorb,kspin} a_{jorb,kspin} a_{iorb,ispin} | Idet > do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,aorb,kspin,ispin) det_tmp(inint,2) = perturb_dets(inint,2,aorb,kspin,ispin) enddo ! you determine the interaction between the excited determinant and the other parent | Jdet > ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{borb,kspin} a_{jorb,kspin} a_{iorb,ispin} | Jdet > ! hja = < det_tmp | H | Jdet > call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp,exc,phase,N_int) if(kspin == ispin)then hja = phase * (active_int(borb,1) - active_int(borb,2) ) else hja = phase * active_int(borb,1) endif !! if(dabs(hja).le.1.d-10)cycle do istate = 1, N_states accu_contrib(istate) += hja * perturb_dets_hij(aorb,kspin,ispin) * delta_e_inv(aorb,kspin,istate) enddo endif logical :: cycle_same_spin_second_order !!!! SECOND ORDER CONTRIBUTIONS !!!! SECOND ORDER CONTRIBTIONS ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{corb,jspin} a_{jorb,jspin} a_{iorb,ispin} | Idet > do jspin = 1, 2 cycle_same_spin_second_order = .False. if(ispin == jspin .and. iorb.le.jorb)then cycle_same_spin_second_order = .True. endif if(ispin .ne. jspin .or. cycle_same_spin_second_order .eqv. .False. )then! condition not to double count do corb = 1, n_act_orb if(perturb_dets_phase(corb,jspin,ispin) .le. -10.d0)cycle do inint = 1, N_int det_tmp(inint,1) = perturb_dets(inint,1,corb,jspin,ispin) det_tmp(inint,2) = perturb_dets(inint,2,corb,jspin,ispin) det_tmp_bis(inint,1) = perturb_dets(inint,1,corb,jspin,ispin) det_tmp_bis(inint,2) = perturb_dets(inint,2,corb,jspin,ispin) enddo ! | det_tmp_bis > = a^{\dagger}_{aorb,kspin} a_{borb,kspin} a_{iorb,kspin} | Idet > call do_mono_excitation(det_tmp_bis,list_act(borb),list_act(aorb),kspin,i_ok) if(i_ok .ne. 1)cycle hia = perturb_dets_hij(corb,jspin,ispin) if(dabs(hia).le.1.d-10)cycle call get_mono_excitation(det_tmp,det_tmp_bis,exc,phase,N_int) hab = fock_operator_local(borb,aorb,kspin) * phase if(dabs(hab).le.1.d-10)cycle call get_double_excitation(psi_det(1,1,idx(jdet)),det_tmp_bis,exc,phase,N_int) if(jspin == ispin)then hjb = phase * (active_int(corb,1) - active_int(corb,2) ) else hjb = phase * active_int(corb,1) endif if(dabs(hjb).le.1.d-10)cycle do istate = 1, N_states accu_contrib(istate)+=hia * delta_e_inv(corb,jspin,istate) & ! | Idet > --> | det_tmp > ! | det_tmp > --> | det_tmp_bis > *hab / (delta_e(corb,jspin,istate) + one_anhil_one_creat(borb,aorb,kspin,kspin,istate)) & *hjb enddo enddo ! jspin endif enddo enddo ! ispin do istate = 1, N_states matrix_2h1p(idx(jdet),idet,istate) += accu_contrib(istate) enddo else if (degree(jdet) == 0 )then ! diagonal part of the dressing : interaction of | Idet > with all the perturbers generated by the excitations ! ! | det_tmp > = a^{\dagger}_{rorb,ispin} a^{\dagger}_{aorb,kspin} a_{jorb,kspin} a_{iorb,ispin} | Idet > accu_contrib = 0.d0 do ispin = 1, 2 do kspin = 1, 2 if(ispin == kspin .and. iorb.le.jorb)cycle ! condition not to double count do a = 1, n_act_orb ! First active contrib_hij = perturb_dets_hij(a,kspin,ispin) * perturb_dets_hij(a,kspin,ispin) if(dabs(contrib_hij).le.1.d-10)cycle do istate = 1, N_states accu_contrib(istate) += contrib_hij * delta_e_inv(a,kspin,istate) enddo enddo enddo enddo do istate =1, N_states matrix_2h1p(idet,idet,istate) += accu_contrib(istate) enddo endif enddo enddo enddo enddo enddo end