diff --git a/deriv_num b/deriv_num
index 7b35aba..064ef5b 100755
Binary files a/deriv_num and b/deriv_num differ
diff --git a/deriv_num.irp.f b/deriv_num.irp.f
index eddbe6d..8debb1c 100644
--- a/deriv_num.irp.f
+++ b/deriv_num.irp.f
@@ -35,7 +35,7 @@ print *, $X_deriv_e(4, $Z)
 print *, ''
 
 SUBST [X, Y, Z]
-factor_en ; ; 1;;
+factor_ee ; ; 1;;
 END_TEMPLATE
 !factor_een ; ; 1;;
 !rescale_een_e ; (1,3,1) ; 1,3,1 ;;
@@ -43,6 +43,8 @@ END_TEMPLATE
 !rescale_een_e ; (1, 2, 2) ; 1, 2, 2 ;;
 !factor_en ; ; 1;;
 !rescale_en ; (1, 2) ; 1, 2 ;;
+!factor_ee ; ; 1;;
+!rescale_ee ; (1, 2) ; 1, 2 ;;
 !elnuc_dist ; (1,1); 1,1 ;;
 !elec_dist  ; (1,2); 1,2 ;;
 
diff --git a/electrons.irp.f b/electrons.irp.f
index 4dfde8a..9e1ea83 100644
--- a/electrons.irp.f
+++ b/electrons.irp.f
@@ -72,7 +72,6 @@ BEGIN_PROVIDER [double precision, asymp_jasb, (2)]
  end do
 
 END_PROVIDER
- 
 
 BEGIN_PROVIDER [double precision, factor_ee]
  implicit none
@@ -108,3 +107,69 @@ BEGIN_PROVIDER [double precision, factor_ee]
  end do
 
 END_PROVIDER
+
+BEGIN_PROVIDER [double precision, factor_ee_deriv_e, (4, nelec) ]
+ implicit none
+ BEGIN_DOC
+ ! Dimensions 1-3 : dx, dy, dz
+ ! Dimension 4 : d2x + d2y + d2z
+ END_DOC
+ integer :: i, ii, j, p
+ double precision :: x, x_inv, y, den, invden, lap1, lap2, lap3, third, spin_fact
+ double precision, dimension(3) :: pow_ser_g
+ double precision, dimension(4) :: dx
+
+ factor_ee_deriv_e = 0.0d0
+ third = 1.0d0 / 3.0d0
+
+ do j = 1 , nelec
+    do i = 1, nelec
+       pow_ser_g = 0.0d0
+       spin_fact = 1.0d0
+       den = 1.0d0 + bord_vect(2) * rescale_ee(i, j)
+       invden = 1.0d0 / den
+       x_inv = 1.0d0 / (rescale_ee(i, j) + 1.0d-18)
+
+       do ii = 1, 4
+          dx(ii) = rescale_ee_deriv_e(ii, j, i)
+       enddo
+
+       if ((i.le.nelec_up .and. j.le.nelec_up) .or. &
+            (i.gt.nelec_up .and. j.gt.nelec_up)) then
+           spin_fact = 0.5d0
+       end if
+
+       lap1 = 0.0d0
+       lap2 = 0.0d0
+       lap3 = 0.0d0
+       do ii = 1, 3
+          x = rescale_ee(i, j)
+          do p = 2, nbord
+             ! p a_{p+1} r[i,j]^(p-1)
+             y = p * bord_vect(p + 1) * x
+             pow_ser_g(ii) += y * dx(ii)
+             ! (p-1) p a_{p+1} r[i,j]^(p-2) r'[i,j]^2
+             lap1 += (p - 1) * y * x_inv * dx(ii) * dx(ii)
+             ! p a_{p+1} r[i,j]^(p-1) r''[i,j]
+             lap2 += y
+             x = x * rescale_ee(i, j)
+          end do
+
+          ! (a1 (-2 a2 r'[i,j]^2+(1+a2 r[i,j]) r''[i,j]))/(1+a2 r[i,j])^3
+          lap3 += -2.0d0 * bord_vect(2) * dx(ii) * dx(ii)
+
+          ! \frac{a1 * r'(i,j)}{(a2 * r(i,j)+1)^2}
+          factor_ee_deriv_e(ii, j) += spin_fact * bord_vect(1) &
+               * dx(ii) * invden * invden + pow_ser_g(ii)
+       enddo
+
+       ii = 4
+       lap2 *= dx(ii) * third
+       lap3 += den * dx(ii)
+       lap3 *= spin_fact * bord_vect(1) * invden * invden * invden
+       factor_ee_deriv_e(ii, j) += lap1 + lap2 + lap3
+
+    end do
+ end do
+
+END_PROVIDER
diff --git a/jastrow b/jastrow
index 55a45b1..0f6c31a 100755
Binary files a/jastrow and b/jastrow differ
diff --git a/nuclei.irp.f b/nuclei.irp.f
index baf959b..cc78b1b 100644
--- a/nuclei.irp.f
+++ b/nuclei.irp.f
@@ -58,7 +58,7 @@ BEGIN_PROVIDER [double precision, factor_en]
  BEGIN_DOC
  ! Electron-nuclei contribution to Jastrow factor
  END_DOC
- integer :: i, a, p, q
+ integer :: i, a, p
  double precision :: pow_ser, x
 
  factor_en = 0.0d0
@@ -87,7 +87,7 @@ BEGIN_PROVIDER [double precision, factor_en_deriv_e, (4, nelec) ]
  ! Dimensions 1-3 : dx, dy, dz
  ! Dimension 4 : d2x + d2y + d2z
  END_DOC
- integer :: i, ii, a, p, q
+ integer :: i, ii, a, p
  double precision :: x, x_inv, y, den, invden, lap1, lap2, lap3, third
  double precision, dimension(3) :: pow_ser_g
  double precision, dimension(4) :: dx
@@ -100,6 +100,7 @@ BEGIN_PROVIDER [double precision, factor_en_deriv_e, (4, nelec) ]
        pow_ser_g = 0.0d0
        den = 1.0d0 + aord_vect(2, typenuc_arr(a)) * rescale_en(i, a)
        invden = 1.0d0 / den
+       x_inv = 1.0d0 / rescale_en(i, a)
 
        do ii = 1, 4
           dx(ii) = rescale_en_deriv_e(ii, i, a)
@@ -110,7 +111,6 @@ BEGIN_PROVIDER [double precision, factor_en_deriv_e, (4, nelec) ]
        lap3 = 0.0d0
        do ii = 1, 3
           x = rescale_en(i, a)
-          x_inv = 1.0d0 / x
           do p = 2, naord
              ! p a_{p+1} r[i,a]^(p-1)
              y = p * aord_vect(p + 1, typenuc_arr(a)) * x
@@ -133,7 +133,7 @@ BEGIN_PROVIDER [double precision, factor_en_deriv_e, (4, nelec) ]
        ii = 4
        lap2 *= dx(ii) * third
        lap3 += den * dx(ii)
-       lap3 = lap3 * aord_vect(1, typenuc_arr(a)) * invden * invden * invden
+       lap3 *= aord_vect(1, typenuc_arr(a)) * invden * invden * invden
        factor_en_deriv_e(ii, i) += lap1 + lap2 + lap3
 
     end do