get_diag_helemen_rs_hub_transcorr_spin Function

    function get_diag_helemen_rs_hub_transcorr_spin(nI) result(hel)
        ! the spin-dependent transcorr diagonal elements
        integer, intent(in) :: nI(nel)
        HElement_t(dp) :: hel

        integer :: i, j, id(nel), ri(3), rj(3), ind_1(3), ind_2(3)

        hel = 0.0_dp

        id = get_spatial(nI)

        do i = 1, nel
            do j = 1, nel
                if (.not. same_spin(nI(i), nI(j))) then
                    ri = lat%get_r_vec(id(i))
                    rj = lat%get_r_vec(id(j))

                    if (is_alpha(nI(i))) then
                        ind_1 = ri - rj
                        ind_2 = rj - ri
                    else
                        ind_1 = rj - ri
                        ind_2 = ri - rj
                    end if
                    hel = hel + 0.5_dp * hop_transcorr_factor_cached_vec(ind_1(1), ind_1(2), ind_1(3)) * &
                          hop_transcorr_factor_cached_vec_m(ind_2(1), ind_2(2), ind_2(3)) * uhub
                end if
            end do
        end do

    end function get_diag_helemen_rs_hub_transcorr_spin