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Comment in 2rdm

This commit is contained in:
Anthony Scemama 2021-05-20 18:19:44 +02:00
parent 1dc2350b32
commit 3ceea5e8b2

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@ -5,18 +5,14 @@ BEGIN_PROVIDER [double precision, two_e_dm_mo, (mo_num,mo_num,mo_num,mo_num)]
!
! <Psi| a^{\dagger}_{i \beta} a^{\dagger}_{j \beta} a_{l \beta} a_{k \beta} |Psi>
!
! WHERE ALL ORBITALS (i,j,k,l) BELONGS TO ALL OCCUPIED ORBITALS : core, inactive and active
! 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
! The normalization (i.e. sum of diagonal elements) is set to $N_{elec} * (N_{elec} - 1)/2$
!
! !!!!! WARNING !!!!! ALL SLATER DETERMINANTS IN PSI_DET MUST BELONG TO AN ACTIVE SPACE DEFINED BY "list_act"
! !!!!! WARNING !!!!! IF "no_core_density" then all elements involving at least one CORE MO are set to zero
! The state-averaged two-electron energy :
!
! !!!!! WARNING !!!!! IF "no_core_density" then all elements involving at least one CORE MO is set to zero
! The two-electron energy of each state can be computed as:
!
! \sum_{i,j,k,l = 1, n_core_inact_act_orb} two_e_dm_mo(i,j,k,l,istate) * < ii jj | kk ll >
!
! with ii = list_core_inact_act(i), jj = list_core_inact_act(j), kk = list_core_inact_act(k), ll = list_core_inact_act(l)
! \sum_{i,j,k,l = 1, mo_num} two_e_dm_mo(i,j,k,l) * < ii jj | kk ll >
END_DOC
two_e_dm_mo = 0.d0
integer :: i,j,k,l,iorb,jorb,korb,lorb,istate