2021-04-17 02:18:57 +02:00
|
|
|
BEGIN_PROVIDER [double precision, two_e_dm_mo, (mo_num,mo_num,mo_num,mo_num)]
|
2021-02-22 12:12:30 +01:00
|
|
|
implicit none
|
|
|
|
BEGIN_DOC
|
2022-01-11 11:25:48 +01:00
|
|
|
! \sum_{\sigma \sigma'}
|
|
|
|
! <Psi| a^{\dagger}_{i \sigma} a^{\dagger}_{j \sigma'} a_{l \sigma'} a_{k \sigma} |Psi>
|
2021-02-22 12:12:30 +01:00
|
|
|
!
|
2021-05-20 18:19:44 +02:00
|
|
|
! where the indices (i,j,k,l) belong to all MOs.
|
2021-02-22 12:12:30 +01:00
|
|
|
!
|
2021-05-20 18:19:44 +02:00
|
|
|
! The normalization (i.e. sum of diagonal elements) is set to $N_{elec} * (N_{elec} - 1)/2$
|
2021-02-22 12:12:30 +01:00
|
|
|
!
|
2021-05-20 18:19:44 +02:00
|
|
|
! !!!!! WARNING !!!!! IF "no_core_density" then all elements involving at least one CORE MO are set to zero
|
|
|
|
! The state-averaged two-electron energy :
|
2021-02-22 12:12:30 +01:00
|
|
|
!
|
2022-01-11 11:25:48 +01:00
|
|
|
! \sum_{i,j,k,l = 1, mo_num} two_e_dm_mo(i,j,k,l) * < kk ll | ii jj >
|
2021-02-22 12:12:30 +01:00
|
|
|
END_DOC
|
|
|
|
two_e_dm_mo = 0.d0
|
|
|
|
integer :: i,j,k,l,iorb,jorb,korb,lorb,istate
|
|
|
|
|
2021-03-14 01:14:12 +01:00
|
|
|
do l=1,mo_num
|
|
|
|
lorb = list_core_inact_act(l)
|
|
|
|
do k=1,mo_num
|
|
|
|
korb = list_core_inact_act(k)
|
|
|
|
do j=1,mo_num
|
|
|
|
jorb = list_core_inact_act(j)
|
|
|
|
do i=1,mo_num
|
|
|
|
iorb = list_core_inact_act(i)
|
2021-04-17 02:18:57 +02:00
|
|
|
two_e_dm_mo(iorb,jorb,korb,lorb) = state_av_full_occ_2_rdm_spin_trace_mo(i,j,k,l)
|
2021-03-14 01:14:12 +01:00
|
|
|
enddo
|
|
|
|
enddo
|
|
|
|
enddo
|
2021-02-22 12:12:30 +01:00
|
|
|
enddo
|
2021-04-17 02:18:57 +02:00
|
|
|
two_e_dm_mo(:,:,:,:) = two_e_dm_mo(:,:,:,:) * 2.d0
|
2021-02-22 12:12:30 +01:00
|
|
|
|
2021-03-14 01:14:12 +01:00
|
|
|
END_PROVIDER
|
|
|
|
|