diff --git a/Basis/F12.ml b/Basis/F12.ml
index cc689cd..26a2fb6 100644
--- a/Basis/F12.ml
+++ b/Basis/F12.ml
@@ -21,7 +21,7 @@ type gaussian_geminal =
   coef_g : 
   *)
 (** Exponent of the geminal *)
-let expo_s = 0.6
+let expo_s = 1.0
 
 
 (** Slater geminal *)
diff --git a/CI/F12CI.ml b/CI/F12CI.ml
index 1e8bdfc..b542be0 100644
--- a/CI/F12CI.ml
+++ b/CI/F12CI.ml
@@ -86,7 +86,7 @@ let is_internal det_space =
         Z.logand aux_mask beta = Z.zero 
 
 
-let dressing_vector gamma aux_basis f12_amplitudes ci =
+let dressing_vector gamma ~frozen_core aux_basis f12_amplitudes ci =
 
 (*
   let i_o1_alfa = h_ij aux_basis in
@@ -113,7 +113,7 @@ let dressing_vector gamma aux_basis f12_amplitudes ci =
 *)
 
   let out_dets =
-    DeterminantSpace.fci_of_mo_basis ~frozen_core:false aux_basis
+    DeterminantSpace.fci_of_mo_basis ~frozen_core aux_basis
     |> DeterminantSpace.determinants_array
     |> Array.to_list
     |> List.filter (fun i -> not (is_internal ci.CI.det_space i))
@@ -189,7 +189,7 @@ let dressing_vector gamma aux_basis f12_amplitudes ci =
 
 let make ~simulation ?(threshold=1.e-12) ~frozen_core ~mo_basis ~aux_basis_filename () =
 
-  let gamma = 1.0 in
+  let gamma = 0.5 in
 
   let mo_num = MOBasis.size mo_basis in
 
@@ -261,7 +261,7 @@ let make ~simulation ?(threshold=1.e-12) ~frozen_core ~mo_basis ~aux_basis_filen
 
     let rec iteration ?(state=1) psi = 
       let delta = 
-         dressing_vector gamma aux_basis (f12_amplitudes psi) ci
+         dressing_vector gamma ~frozen_core aux_basis (f12_amplitudes psi) ci
       in
 
       let f = 1.0 /. psi.{1,1} in