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qp2/src/two_body_rdm/two_e_dm_mo.irp.f

39 lines
1.3 KiB
Fortran

BEGIN_PROVIDER [double precision, two_e_dm_mo, (mo_num,mo_num,mo_num,mo_num)]
implicit none
BEGIN_DOC
! \sum_{\sigma \sigma'}
! <Psi| a^{\dagger}_{i \sigma} a^{\dagger}_{j \sigma'} a_{l \sigma'} a_{k \sigma} |Psi>
!
! where the indices (i,j,k,l) belong to all MOs.
!
! The normalization (i.e. sum of diagonal elements) is set to $N_{elec} * (N_{elec} - 1)/2$
!
! !!!!! WARNING !!!!! IF "no_core_density" then all elements involving at least one CORE MO are set to zero
! The state-averaged two-electron energy :
!
! \sum_{i,j,k,l = 1, mo_num} two_e_dm_mo(i,j,k,l) * < kk ll | ii jj >
END_DOC
two_e_dm_mo = 0.d0
integer :: i,j,k,l,iorb,jorb,korb,lorb,istate
!$OMP PARALLEL DO PRIVATE(i,j,k,l,iorb,jorb,korb,lorb) &
!$OMP DEFAULT(NONE) SHARED(n_core_inact_act_orb, list_core_inact_act, &
!$OMP two_e_dm_mo, state_av_full_occ_2_rdm_spin_trace_mo)
do l=1,n_core_inact_act_orb
lorb = list_core_inact_act(l)
do k=1,n_core_inact_act_orb
korb = list_core_inact_act(k)
do j=1,n_core_inact_act_orb
jorb = list_core_inact_act(j)
do i=1,n_core_inact_act_orb
iorb = list_core_inact_act(i)
two_e_dm_mo(iorb,jorb,korb,lorb) = state_av_full_occ_2_rdm_spin_trace_mo(i,j,k,l)
enddo
enddo
enddo
enddo
!$OMP END PARALLEL DO
END_PROVIDER