Add_RDM_HFConnections_Norm Subroutine

    subroutine Add_RDM_HFConnections_Norm(spawn, one_rdms, iLutJ, nJ, AvSignJ, AvSignHF, walkExcitLevel, IterRDM)

        ! This is called when we run over all TotWalkers in CurrentDets.
        ! It is called for each CurrentDet which is a single or double of the HF.
        ! It explicitly adds in the HF - S/D connection, as if the HF were D_i and
        ! the single or double D_j. This is the standard full space RDM calc (No HPHF).
        ! In this case the diagonal elements wll already be taken care of.

        use FciMCData, only: HFDet_True
        use rdm_data, only: one_rdm_t

        type(rdm_spawn_t), intent(inout) :: spawn
        type(one_rdm_t), intent(inout) :: one_rdms(:)
        integer(n_int), intent(in) :: iLutJ(0:NIfTot)
        integer, intent(in) :: nJ(nel)
        real(dp), intent(in) :: AvSignJ(:), AvSignHF(:)
        integer, intent(in) :: walkExcitLevel
        integer, intent(in) :: IterRDM(:)
#ifdef DEBUG_
        character(*), parameter :: this_routine = "Add_RDM_HFConnections_Norm"
#endif

        integer(n_int) :: iUnused

        ! If we have a single or double, add in the connection to the HF,
        ! symmetrically.
        if ((walkExcitLevel == 1) .or. (walkExcitLevel == 2)) then
            call Add_RDM_From_IJ_Pair(spawn, one_rdms, HFDet_True, nJ, AvSignHF(2::2), IterRDM*AvSignJ(1::2))
            call Add_RDM_From_IJ_Pair(spawn, one_rdms, nJ, HFDet_True, AvSignJ(2::2), IterRDM*AvSignHF(1::2))
        end if

        ! Eliminate compiler warnings.
        iUnused = ilutJ(0)

    end subroutine Add_RDM_HFConnections_Norm