diff --git a/plugins/Hartree_Fock/SCF.irp.f b/plugins/Hartree_Fock/SCF.irp.f
index 864e9f3f..f21c7399 100644
--- a/plugins/Hartree_Fock/SCF.irp.f
+++ b/plugins/Hartree_Fock/SCF.irp.f
@@ -48,10 +48,7 @@ subroutine run
    
   E0 = HF_energy 
 
-  thresh_SCF = 1.d-10
-  call damping_SCF
   mo_label = "Canonical"
-  TOUCH mo_label mo_coef
-  call save_mos
+  call damping_SCF
   
 end
diff --git a/plugins/Hartree_Fock/damping_SCF.irp.f b/plugins/Hartree_Fock/damping_SCF.irp.f
index d7d9c2bf..c7c005c9 100644
--- a/plugins/Hartree_Fock/damping_SCF.irp.f
+++ b/plugins/Hartree_Fock/damping_SCF.irp.f
@@ -86,7 +86,7 @@ subroutine damping_SCF
       if ((E_half > E).and.(E_new < E)) then
         lambda = 1.d0
         exit
-      else if ((E_half > E).and.(lambda > 5.d-2)) then
+      else if ((E_half > E).and.(lambda > 5.d-4)) then
         lambda = 0.5d0 * lambda
         E_new = E_half
       else
diff --git a/plugins/QmcChem/target_pt2_qmc.irp.f b/plugins/QmcChem/target_pt2_qmc.irp.f
index e5142a73..6e6d2a60 100644
--- a/plugins/QmcChem/target_pt2_qmc.irp.f
+++ b/plugins/QmcChem/target_pt2_qmc.irp.f
@@ -93,7 +93,7 @@ subroutine compute_energy(psi_bilinear_matrix_values_save, E, m, norm)
     m = 0
     !$OMP PARALLEL DEFAULT(SHARED) PRIVATE(k,l,det_i,det_j,ci,cj,hij) REDUCTION(+:norm,m,num)
     allocate( det_i(N_int,2), det_j(N_int,2))
-    !$OMP DO 
+    !$OMP DO schedule(guided)
     do k=1,n_det
       if (psi_bilinear_matrix_values_save(k) == 0.d0) then
         cycle
diff --git a/scripts/utility/is_master_repository.py b/scripts/utility/is_master_repository.py
index 9ead14a2..da5fb56f 100755
--- a/scripts/utility/is_master_repository.py
+++ b/scripts/utility/is_master_repository.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 
 import subprocess
-pipe = subprocess.Popen("git config --local --get remote.origin.url", \
+pipe = subprocess.Popen("git config --get remote.origin.url", \
               shell=True, stdout=subprocess.PIPE)
 result = pipe.stdout.read()
 is_master_repository = "LCPQ/quantum_package" in result
diff --git a/src/Determinants/H_apply.irp.f b/src/Determinants/H_apply.irp.f
index 6e2b3a5a..7e9861fe 100644
--- a/src/Determinants/H_apply.irp.f
+++ b/src/Determinants/H_apply.irp.f
@@ -2,11 +2,11 @@ use bitmasks
 use omp_lib
 
 type H_apply_buffer_type
-integer                        :: N_det
-integer                        :: sze
-integer(bit_kind), pointer     :: det(:,:,:)
-double precision , pointer     :: coef(:,:)
-double precision , pointer     :: e2(:,:)
+  integer                        :: N_det
+  integer                        :: sze
+  integer(bit_kind), pointer     :: det(:,:,:)
+  double precision , pointer     :: coef(:,:)
+  double precision , pointer     :: e2(:,:)
 end type H_apply_buffer_type
 
 type(H_apply_buffer_type), pointer :: H_apply_buffer(:)
@@ -41,6 +41,15 @@ type(H_apply_buffer_type), pointer :: H_apply_buffer(:)
     call omp_init_lock(H_apply_buffer_lock(1,iproc))
     !$OMP END PARALLEL
   endif
+  do iproc=2,nproc-1
+    if (.not.associated(H_apply_buffer(iproc)%det)) then
+      print *,  ' ===================== Error =================== '
+      print *,  'H_apply_buffer_allocated  should be provided outside'
+      print *,  'of an OpenMP section'
+      print *,  ' =============================================== '
+      stop
+    endif
+  enddo
   
 END_PROVIDER
 
@@ -111,7 +120,6 @@ subroutine copy_H_apply_buffer_to_wf
   double precision, allocatable  :: buffer_coef(:,:)
   integer                        :: i,j,k
   integer                        :: N_det_old
-  integer                        :: iproc
   
   PROVIDE H_apply_buffer_allocated
   
@@ -158,7 +166,7 @@ subroutine copy_H_apply_buffer_to_wf
   enddo
   !$OMP PARALLEL DEFAULT(SHARED)                                     &
       !$OMP PRIVATE(j,k,i) FIRSTPRIVATE(N_det_old)                   &
-      !$OMP SHARED(N_int,H_apply_buffer,psi_det,psi_coef,N_states)
+      !$OMP SHARED(N_int,H_apply_buffer,psi_det,psi_coef,N_states,psi_det_size)
   j=0
   !$ j=omp_get_thread_num()
   do k=0,j-1
diff --git a/src/Determinants/davidson.irp.f b/src/Determinants/davidson.irp.f
index bceb145a..fd2efcf9 100644
--- a/src/Determinants/davidson.irp.f
+++ b/src/Determinants/davidson.irp.f
@@ -90,51 +90,70 @@ end function
 
 subroutine tamiser(key, idx, no, n, Nint, N_key)
   use bitmasks
-  
   implicit none
-  integer(bit_kind),intent(inout)       :: key(Nint, 2, N_key)
+  
+  BEGIN_DOC
+! Uncodumented : TODO
+  END_DOC
   integer,intent(in)                    :: no, n, Nint, N_key
+  integer(bit_kind),intent(inout)       :: key(Nint, 2, N_key)
   integer,intent(inout)                 :: idx(N_key)
   integer                               :: k,j,tmpidx
   integer(bit_kind)                     :: tmp(Nint, 2)
   logical                               :: det_inf
+  integer                               :: ni
   
   k = no
   j = 2*k
   do while(j <= n)
-    if(j < n .and. det_inf(key(:,:,j), key(:,:,j+1), Nint)) then
-      j = j+1
-    end if
-    if(det_inf(key(:,:,k), key(:,:,j), Nint)) then
-      tmp(:,:) = key(:,:,k)
-      key(:,:,k) = key(:,:,j)
-      key(:,:,j) = tmp(:,:)
+    if(j < n) then
+      if (det_inf(key(1,1,j), key(1,1,j+1), Nint)) then
+        j = j+1
+      endif
+    endif
+    if(det_inf(key(1,1,k), key(1,1,j), Nint)) then
+      do ni=1,Nint
+        tmp(ni,1)   = key(ni,1,k)
+        tmp(ni,2)   = key(ni,2,k)
+        key(ni,1,k) = key(ni,1,j)
+        key(ni,2,k) = key(ni,2,j)
+        key(ni,1,j) = tmp(ni,1)
+        key(ni,2,j) = tmp(ni,2)
+      enddo
       tmpidx = idx(k)
       idx(k) = idx(j)
       idx(j) = tmpidx
       k = j
-      j = 2*k
+      j = k+k
     else
       return
-    end if
-  end do
+    endif
+  enddo
 end subroutine
 
 
 subroutine sort_dets_ba_v(key_in, key_out, idx, shortcut, version, N_key, Nint)
   use bitmasks
   implicit none
-  integer(bit_kind),intent(in)          :: key_in(Nint,2,N_key)
-  integer(bit_kind)                     :: key(Nint,2,N_key)
-  integer(bit_kind),intent(out)         :: key_out(Nint,N_key)
-  integer,intent(out)                   :: idx(N_key)
-  integer,intent(out)                   :: shortcut(0:N_key+1)
-    integer(bit_kind),intent(out)       :: version(Nint,N_key+1)
-  integer, intent(in)                   :: Nint, N_key
-  integer(bit_kind)                     :: tmp(Nint, 2,N_key)
+  integer, intent(in)            :: Nint, N_key
+  integer(bit_kind),intent(in)   :: key_in(Nint,2,N_key)
+  integer(bit_kind)              :: key(Nint,2,N_key)
+  integer(bit_kind),intent(out)  :: key_out(Nint,N_key)
+  integer,intent(out)            :: idx(N_key)
+  integer,intent(out)            :: shortcut(0:N_key+1)
+  integer(bit_kind),intent(out)  :: version(Nint,N_key+1)
+  integer(bit_kind)              :: tmp(Nint, 2,N_key)
+  integer                        :: i,ni
   
-  key(:,1,:N_key) = key_in(:,2,:N_key)
-  key(:,2,:N_key) = key_in(:,1,:N_key)
+  BEGIN_DOC
+! Uncodumented : TODO
+  END_DOC
+  do i=1,N_key
+    do ni=1,Nint
+      key(ni,1,i) = key_in(ni,2,i)
+      key(ni,2,i) = key_in(ni,1,i)
+    enddo
+  enddo
   
 
   call sort_dets_ab_v(key, key_out, idx, shortcut, version, N_key, Nint)
@@ -146,18 +165,24 @@ subroutine sort_dets_ab_v(key_in, key_out, idx, shortcut, version, N_key, Nint)
   use bitmasks
   implicit none
   
+  BEGIN_DOC
+! Uncodumented : TODO
+  END_DOC
+  integer, intent(in)                   :: Nint, N_key
   integer(bit_kind),intent(in)          :: key_in(Nint,2,N_key)
   integer(bit_kind)                     :: key(Nint,2,N_key)
   integer(bit_kind),intent(out)         :: key_out(Nint,N_key)
   integer,intent(out)                   :: idx(N_key)
   integer,intent(out)                   :: shortcut(0:N_key+1)
   integer(bit_kind),intent(out)         :: version(Nint,N_key+1)
-  integer, intent(in)                   :: Nint, N_key
   integer(bit_kind)                     :: tmp(Nint, 2)
   integer                               :: tmpidx,i,ni
   
-  key(:,:,:) = key_in(:,:,:)
   do i=1,N_key
+    do ni=1,Nint
+      key(ni,1,i) = key_in(ni,1,i)
+      key(ni,2,i) = key_in(ni,2,i)
+    enddo
     idx(i) = i
   end do
   
@@ -166,9 +191,14 @@ subroutine sort_dets_ab_v(key_in, key_out, idx, shortcut, version, N_key, Nint)
   end do
   
   do i=N_key,2,-1
-    tmp(:,:) = key(:,:,i)
-    key(:,:,i) = key(:,:,1)
-    key(:,:,1) = tmp(:,:)
+    do ni=1,Nint
+      tmp(ni,1) = key(ni,1,i)
+      tmp(ni,2) = key(ni,2,i)
+      key(ni,1,i) = key(ni,1,1)
+      key(ni,2,i) = key(ni,2,1)
+      key(ni,1,1) = tmp(ni,1)
+      key(ni,2,1) = tmp(ni,2)
+    enddo
     tmpidx = idx(i)
     idx(i) = idx(1)
     idx(1) = tmpidx
@@ -177,7 +207,9 @@ subroutine sort_dets_ab_v(key_in, key_out, idx, shortcut, version, N_key, Nint)
   
   shortcut(0) = 1
   shortcut(1) = 1
-  version(:,1) = key(:,1,1)
+  do ni=1,Nint
+    version(ni,1) = key(ni,1,1)
+  enddo
   do i=2,N_key
     do ni=1,nint
       if(key(ni,1,i) /= key(ni,1,i-1)) then
@@ -189,15 +221,22 @@ subroutine sort_dets_ab_v(key_in, key_out, idx, shortcut, version, N_key, Nint)
     end do
   end do
   shortcut(shortcut(0)+1) = N_key+1
-  key_out(:,:) = key(:,2,:)
+  do i=1,N_key
+    do ni=1,Nint
+      key_out(ni,i) = key(ni,2,i)
+    enddo
+  enddo
 end subroutine
 
-c
 
 subroutine sort_dets_ab(key, idx, shortcut, N_key, Nint)
   use bitmasks
   implicit none
   
+  
+  BEGIN_DOC
+! Uncodumented : TODO
+  END_DOC
   integer(bit_kind),intent(inout)       :: key(Nint,2,N_key)
   integer,intent(out)                   :: idx(N_key)
   integer,intent(out)                   :: shortcut(0:N_key+1)
@@ -214,9 +253,15 @@ subroutine sort_dets_ab(key, idx, shortcut, N_key, Nint)
   end do
   
   do i=N_key,2,-1
-    tmp(:,:) = key(:,:,i)
-    key(:,:,i) = key(:,:,1)
-    key(:,:,1) = tmp(:,:)
+    do ni=1,Nint
+      tmp(ni,1) = key(ni,1,i)
+      tmp(ni,2) = key(ni,2,i)
+      key(ni,1,i) = key(ni,1,1)
+      key(ni,2,i) = key(ni,2,1)
+      key(ni,1,1) = tmp(ni,1)
+      key(ni,2,1) = tmp(ni,2)
+    enddo
+
     tmpidx = idx(i)
     idx(i) = idx(1)
     idx(1) = tmpidx
diff --git a/src/Determinants/determinants.irp.f b/src/Determinants/determinants.irp.f
index d1c36163..5fe18c49 100644
--- a/src/Determinants/determinants.irp.f
+++ b/src/Determinants/determinants.irp.f
@@ -8,6 +8,7 @@ BEGIN_PROVIDER [ integer, N_det ]
  logical                        :: exists
  character*64                   :: label
  PROVIDE ezfio_filename
+ PROVIDE nproc
  if (read_wf) then
    call ezfio_has_determinants_n_det(exists)
    if (exists) then
diff --git a/src/Determinants/guess_lowest_state.irp.f b/src/Determinants/guess_lowest_state.irp.f
new file mode 100644
index 00000000..f6d0a004
--- /dev/null
+++ b/src/Determinants/guess_lowest_state.irp.f
@@ -0,0 +1,162 @@
+program first_guess
+  use bitmasks
+  implicit none
+  BEGIN_DOC
+  ! Select all the determinants with the lowest energy as a starting point.
+  END_DOC
+  integer                        :: i,j
+  double precision, allocatable  :: orb_energy(:)
+  double precision               :: E
+  integer, allocatable           :: kept(:)
+  integer                        :: nelec_kept(2)
+  character                      :: occ_char, keep_char
+  
+  PROVIDE H_apply_buffer_allocated psi_det
+  allocate (orb_energy(mo_tot_num), kept(0:mo_tot_num))
+  nelec_kept(1:2) = 0
+  kept(0) = 0
+
+  print *,  'Orbital energies'
+  print *,  '================'
+  print *,  ''
+  do i=1,mo_tot_num
+    keep_char = ' '
+    occ_char = '-'
+    orb_energy(i) = mo_mono_elec_integral(i,i)
+    do j=1,elec_beta_num
+      if (i==j) cycle
+      orb_energy(i) += mo_bielec_integral_jj_anti(i,j)
+    enddo
+    do j=1,elec_alpha_num
+      orb_energy(i) += mo_bielec_integral_jj(i,j)
+    enddo
+    if ( (orb_energy(i) > -.5d0).and.(orb_energy(i) < .1d0) ) then
+      kept(0) += 1
+      keep_char = 'X'
+      kept( kept(0) ) = i
+      if (i <= elec_beta_num) then
+        nelec_kept(2) += 1
+      endif
+      if (i <= elec_alpha_num) then
+        nelec_kept(1) += 1
+      endif
+    endif
+    if (i <= elec_alpha_num) then
+      if (i <= elec_beta_num) then
+        occ_char = '#'
+      else
+        occ_char = '+'
+      endif
+    endif
+    print '(I4, 3X, A, 3X, F10.6, 3X, A)', i, occ_char, orb_energy(i), keep_char 
+  enddo
+
+  
+  integer, allocatable           :: list  (:,:)
+  integer(bit_kind), allocatable :: string(:,:)
+  allocate ( list(N_int*bit_kind_size,2), string(N_int,2) )
+
+  string = ref_bitmask
+  call bitstring_to_list( string(1,1), list(1,1), elec_alpha_num, N_int)
+  call bitstring_to_list( string(1,2), list(1,2), elec_beta_num , N_int)
+
+  psi_det_alpha_unique(:,1) = string(:,1)
+  psi_det_beta_unique (:,1) = string(:,2)
+  N_det_alpha_unique = 1
+  N_det_beta_unique  = 1
+
+  integer :: i1,i2,i3,i4,i5,i6,i7,i8,i9
+
+  psi_det_size = kept(0)**(nelec_kept(1)+nelec_kept(2))
+  print *,  kept(0), nelec_kept(:)
+  call write_int(6,psi_det_size,'psi_det_size')
+  TOUCH psi_det_size
+
+BEGIN_SHELL [ /usr/bin/python ]
+
+template_alpha_ext = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_alpha_num-%(i)d,1) = kept(%(i2)s)
+  call list_to_bitstring( string(1,1), list(1,1), elec_alpha_num, N_int)
+"""
+
+template_alpha = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_alpha_num-%(i)d,1) = kept(%(i2)s)
+  call list_to_bitstring( string(1,1), list(1,1), elec_alpha_num, N_int)
+  N_det_alpha_unique += 1
+  psi_det_alpha_unique(:,N_det_alpha_unique) = string(:,1)
+"""
+
+template_beta_ext = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_beta_num-%(i)d,2) = kept(%(i2)s)
+  call list_to_bitstring( string(1,2), list(1,2), elec_beta_num, N_int)
+"""
+template_beta = """
+do %(i2)s = %(i1)s-1,1,-1
+  list(elec_beta_num-%(i)d,2) = kept(%(i2)s)
+  call list_to_bitstring( string(1,2), list(1,2), elec_beta_num, N_int)
+  N_det_beta_unique += 1
+  psi_det_beta_unique(:,N_det_beta_unique) = string(:,2)
+"""
+
+def write(template_ext,template,imax):
+    print "case(%d)"%(imax)
+    def aux(i2,i1,i,j):
+        if (i==imax-1):
+          print template%locals()
+        else:
+          print template_ext%locals()
+        i += 1
+        j -= 1
+        if (i != imax):
+            i1 = "i%d"%(i)
+            i2 = "i%d"%(i+1)
+            aux(i2,i1,i,j)
+        print "enddo"
+
+    i2 = "i1"
+    i1 = "kept(0)+1"
+    i  = 0
+    aux(i2,i1,i,imax)
+
+def main():
+    print """
+    select case (nelec_kept(1))
+      case(0)
+        continue
+    """
+    for imax in range(1,10):
+        write(template_alpha_ext,template_alpha,imax)
+
+    print """
+    end select
+
+    select case (nelec_kept(2))
+      case(0)
+        continue
+    """
+    for imax in range(1,10):
+        write(template_beta_ext,template_beta,imax)
+    print "end select"
+
+main()
+
+END_SHELL
+
+  TOUCH N_det_alpha_unique N_det_beta_unique psi_det_alpha_unique psi_det_beta_unique
+  call create_wf_of_psi_bilinear_matrix(.False.)
+  call diagonalize_ci
+  j= N_det
+  do i=1,N_det
+    if (psi_average_norm_contrib_sorted(i) < 1.d-6) then
+       j = i-1
+       exit
+    endif
+!  call debug_det(psi_det_sorted(1,1,i),N_int)
+  enddo
+  call save_wavefunction_general(j,N_states,psi_det_sorted,size(psi_coef_sorted,1),psi_coef_sorted)
+
+  deallocate(orb_energy, kept, list, string)
+end
diff --git a/src/Determinants/program_initial_determinants.irp.f b/src/Determinants/program_initial_determinants.irp.f
deleted file mode 100644
index 6375af22..00000000
--- a/src/Determinants/program_initial_determinants.irp.f
+++ /dev/null
@@ -1,138 +0,0 @@
-program pouet
- implicit none
- print*,'HF energy = ',ref_bitmask_energy + nuclear_repulsion
- call routine
-
-end
-subroutine routine 
- use bitmasks
- implicit none
- integer :: i,j,k,l
- double precision :: hij,get_mo_bielec_integral
- double precision :: hmono,h_bi_ispin,h_bi_other_spin
- integer(bit_kind),allocatable  :: key_tmp(:,:)
- integer, allocatable :: occ(:,:)
- integer       :: n_occ_alpha, n_occ_beta
- ! First checks 
- print*,'N_int            = ',N_int
- print*,'mo_tot_num       = ',mo_tot_num
- print*,'mo_tot_num / 64+1= ',mo_tot_num/64+1
- ! We print the HF determinant
- do i = 1, N_int
-  print*,'ref_bitmask(i,1) = ',ref_bitmask(i,1)
-  print*,'ref_bitmask(i,2) = ',ref_bitmask(i,2)
- enddo
- print*,''
- print*,'Hartree Fock determinant ...'
- call debug_det(ref_bitmask,N_int)
- allocate(key_tmp(N_int,2))
- ! We initialize key_tmp to the Hartree Fock one
- key_tmp = ref_bitmask
- integer :: i_hole,i_particle,ispin,i_ok,other_spin
- ! We do a mono excitation on the top of the HF determinant
- write(*,*)'Enter the (hole, particle) couple for the mono excitation ...'
- read(5,*)i_hole,i_particle
-!!i_hole = 4
-!!i_particle = 20
- write(*,*)'Enter the ispin variable ...'
- write(*,*)'ispin = 1 ==> alpha '
- write(*,*)'ispin = 2 ==> beta  '
- read(5,*)ispin
- if(ispin == 1)then
-  other_spin = 2
- else if(ispin == 2)then 
-  other_spin = 1
- else
-  print*,'PB !! '
-  print*,'ispin must be 1 or 2 !'
-  stop
- endif
-!!ispin = 1
- call do_mono_excitation(key_tmp,i_hole,i_particle,ispin,i_ok)
- ! We check if it the excitation was possible with "i_ok"
- if(i_ok == -1)then
-  print*,'i_ok = ',i_ok
-  print*,'You can not do this excitation because of Pauli principle ...'
-  print*,'check your hole particle couple, there must be something wrong ...'
-  stop
-
- endif
- print*,'New det = '
- call debug_det(key_tmp,N_int)
- call i_H_j(key_tmp,ref_bitmask,N_int,hij)
- ! We calculate the H matrix element between the new determinant and HF
- print*,'<D_i|H|D_j>    = ',hij
- print*,''
- print*,''
- print*,'Recalculating it old school style ....'
- print*,''
- print*,''
- ! We recalculate this old school style !!!
- ! Mono electronic part
- hmono = mo_mono_elec_integral(i_hole,i_particle)
- print*,''
- print*,'Mono electronic part '
- print*,''
- print*,'<D_i|h(1)|D_j> = ',hmono
- h_bi_ispin = 0.d0
- h_bi_other_spin = 0.d0
- print*,''
- print*,'Getting all the info for the calculation of the bi electronic part ...'
- print*,''
- allocate (occ(N_int*bit_kind_size,2))
- ! We get the occupation of the alpha electrons in occ(:,1)
- call bitstring_to_list(key_tmp(1,1), occ(1,1), n_occ_alpha, N_int)
- print*,'n_occ_alpha    = ',n_occ_alpha
- print*,'elec_alpha_num = ',elec_alpha_num
- ! We get the occupation of the beta electrons in occ(:,2)
- call bitstring_to_list(key_tmp(1,2), occ(1,2), n_occ_beta, N_int)
- print*,'n_occ_beta    = ',n_occ_beta
- print*,'elec_beta_num = ',elec_beta_num
- ! We print the occupation of the alpha electrons 
- print*,'Alpha electrons !'
- do i = 1, n_occ_alpha
-  print*,'i = ',i
-  print*,'occ(i,1) = ',occ(i,1)
- enddo
- ! We print the occupation of the beta electrons 
- print*,'Alpha electrons !'
- do i = 1, n_occ_beta
-  print*,'i = ',i
-  print*,'occ(i,2) = ',occ(i,2)
- enddo
- integer                        :: exc(0:2,2,2),degree,h1,p1,h2,p2,s1,s2
- double precision :: phase
-
- call get_excitation_degree(key_tmp,ref_bitmask,degree,N_int)
- print*,'degree = ',degree
- call get_mono_excitation(ref_bitmask,key_tmp,exc,phase,N_int)
- call decode_exc(exc,degree,h1,p1,h2,p2,s1,s2)
- print*,'h1  = ',h1
- print*,'p1  = ',p1
- print*,'s1  = ',s1
- print*,'phase = ',phase
- do i = 1, elec_num_tab(ispin)
-  integer :: orb_occupied
-  orb_occupied = occ(i,ispin)
-  h_bi_ispin += get_mo_bielec_integral(i_hole,orb_occupied,i_particle,orb_occupied,mo_integrals_map) & 
-               -get_mo_bielec_integral(i_hole,i_particle,orb_occupied,orb_occupied,mo_integrals_map)
- enddo
- print*,'h_bi_ispin = ',h_bi_ispin
-
- do i = 1, elec_num_tab(other_spin)
-  orb_occupied = occ(i,other_spin)
-  h_bi_other_spin += get_mo_bielec_integral(i_hole,orb_occupied,i_particle,orb_occupied,mo_integrals_map) 
- enddo
- print*,'h_bi_other_spin  = ',h_bi_other_spin
- print*,'h_bi_ispin + h_bi_other_spin = ',h_bi_ispin + h_bi_other_spin 
-
- print*,'Total matrix element =  ',phase*(h_bi_ispin + h_bi_other_spin + hmono)
-!i = 1
-!j = 1
-!k = 1
-!l = 1
-!hij = get_mo_bielec_integral(i,j,k,l,mo_integrals_map)
-!print*,'<ij|kl> = ',hij
-
-
-end
diff --git a/src/Determinants/s2.irp.f b/src/Determinants/s2.irp.f
index e836d25d..573f094f 100644
--- a/src/Determinants/s2.irp.f
+++ b/src/Determinants/s2.irp.f
@@ -109,81 +109,82 @@ end
 subroutine get_s2_u0(psi_keys_tmp,psi_coefs_tmp,n,nmax,s2)
   implicit none
   use bitmasks
-  integer(bit_kind), intent(in) :: psi_keys_tmp(N_int,2,nmax)
-  integer, intent(in) :: n,nmax
-  double precision, intent(in) :: psi_coefs_tmp(nmax)
-  double precision, intent(out) :: s2
-  double precision :: s2_tmp
-  integer :: i,j,l,jj,ii
+  integer(bit_kind), intent(in)  :: psi_keys_tmp(N_int,2,nmax)
+  integer, intent(in)            :: n,nmax
+  double precision, intent(in)   :: psi_coefs_tmp(nmax)
+  double precision, intent(out)  :: s2
+  double precision               :: s2_tmp
+  integer                        :: i,j,l,jj,ii
   integer, allocatable           :: idx(:)
- 
+  
   integer                        :: shortcut(0:n+1), sort_idx(n)
   integer(bit_kind)              :: sorted(N_int,n), version(N_int,n)
   integer                        :: sh, sh2, ni, exa, ext, org_i, org_j, endi, pass
   double precision               :: davidson_threshold_bis
-
+  
   !PROVIDE davidson_threshold
   
   s2 = 0.d0
   davidson_threshold_bis = davidson_threshold
-  !$OMP PARALLEL DEFAULT(NONE)                                        &
-      !$OMP PRIVATE(i,j,s2_tmp,idx,sh, sh2, ni, exa, ext, org_i, org_j, endi, pass)                                   &
+  call sort_dets_ab_v(psi_keys_tmp, sorted, sort_idx, shortcut, version, n, N_int)
+  
+  !$OMP PARALLEL DEFAULT(NONE)                                       &
+      !$OMP PRIVATE(i,j,s2_tmp,sh, sh2, ni, exa, ext, org_i, org_j, endi, pass)&
       !$OMP SHARED(n,psi_coefs_tmp,psi_keys_tmp,N_int,davidson_threshold,shortcut,sorted,sort_idx,version)&
       !$OMP REDUCTION(+:s2)
-  allocate(idx(0:n))
-  
-  
-  !$OMP SINGLE
-  call sort_dets_ab_v(psi_keys_tmp, sorted, sort_idx, shortcut, version, n, N_int)
-  !$OMP END SINGLE
   
   !$OMP DO SCHEDULE(dynamic)
   do sh=1,shortcut(0)
-  
-  do sh2=1,sh
-    exa = 0
-    do ni=1,N_int
-      exa += popcnt(xor(version(ni,sh), version(ni,sh2)))
-    end do
-    if(exa > 2) then
-      cycle
-    end if
     
-    do i=shortcut(sh),shortcut(sh+1)-1
-      if(sh==sh2) then
-        endi = i-1
-      else
-        endi = shortcut(sh2+1)-1
+    do sh2=1,sh
+      exa = 0
+      do ni=1,N_int
+        exa += popcnt(xor(version(ni,sh), version(ni,sh2)))
+      end do
+      if(exa > 2) then
+        cycle
       end if
       
-      do j=shortcut(sh2),endi
-        ext = exa
-        do ni=1,N_int
-          ext += popcnt(xor(sorted(ni,i), sorted(ni,j)))
-        end do
-        if(ext <= 4) then
-          org_i = sort_idx(i)
-          org_j = sort_idx(j)
-          
-          if ( dabs(psi_coefs_tmp(org_j)) + dabs(psi_coefs_tmp(org_i))            &
-                > davidson_threshold ) then
-            call get_s2(psi_keys_tmp(1,1,org_i),psi_keys_tmp(1,1,org_j),s2_tmp,N_int)
-            s2 = s2 + psi_coefs_tmp(org_i)*psi_coefs_tmp(org_j)*s2_tmp
-          endif
+      do i=shortcut(sh),shortcut(sh+1)-1
+        if(sh==sh2) then
+          endi = i-1
+        else
+          endi = shortcut(sh2+1)-1
         end if
+        
+        do j=shortcut(sh2),endi
+          ext = exa
+          do ni=1,N_int
+            ext += popcnt(xor(sorted(ni,i), sorted(ni,j)))
+          end do
+          if(ext <= 4) then
+            org_i = sort_idx(i)
+            org_j = sort_idx(j)
+            
+            if ( dabs(psi_coefs_tmp(org_j)) + dabs(psi_coefs_tmp(org_i))&
+                  > davidson_threshold ) then
+              call get_s2(psi_keys_tmp(1,1,org_i),psi_keys_tmp(1,1,org_j),s2_tmp,N_int)
+              s2 = s2 + psi_coefs_tmp(org_i)*psi_coefs_tmp(org_j)*s2_tmp
+            endif
+          end if
+        end do
       end do
     end do
-  end do
   enddo
   !$OMP END DO
   
-  !$OMP SINGLE
+  !$OMP END PARALLEL
+  
   call sort_dets_ba_v(psi_keys_tmp, sorted, sort_idx, shortcut, version, n, N_int)
-  !$OMP END SINGLE
+  
+  !$OMP PARALLEL DEFAULT(NONE)                                       &
+      !$OMP PRIVATE(i,j,s2_tmp,sh, sh2, ni, exa, ext, org_i, org_j, endi, pass)&
+      !$OMP SHARED(n,psi_coefs_tmp,psi_keys_tmp,N_int,davidson_threshold,shortcut,sorted,sort_idx,version)&
+      !$OMP REDUCTION(+:s2)
   
   !$OMP DO SCHEDULE(dynamic)
   do sh=1,shortcut(0)
-    do i=shortcut(sh),shortcut(sh+1)-1    
+    do i=shortcut(sh),shortcut(sh+1)-1
       do j=shortcut(sh),i-1
         ext = 0
         do ni=1,N_int
@@ -193,25 +194,24 @@ subroutine get_s2_u0(psi_keys_tmp,psi_coefs_tmp,n,nmax,s2)
           org_i = sort_idx(i)
           org_j = sort_idx(j)
           
-          if ( dabs(psi_coefs_tmp(org_j)) + dabs(psi_coefs_tmp(org_i))            &
+          if ( dabs(psi_coefs_tmp(org_j)) + dabs(psi_coefs_tmp(org_i))&
                 > davidson_threshold ) then
             call get_s2(psi_keys_tmp(1,1,org_i),psi_keys_tmp(1,1,org_j),s2_tmp,N_int)
             s2 = s2 + psi_coefs_tmp(org_i)*psi_coefs_tmp(org_j)*s2_tmp
           endif
         end if
       end do
-    end do          
+    end do
   enddo
   !$OMP END DO
   
- deallocate(idx)
- !$OMP END PARALLEL
- s2 = s2+s2
- do i=1,n
-   call get_s2(psi_keys_tmp(1,1,i),psi_keys_tmp(1,1,i),s2_tmp,N_int)
-   s2 = s2 + psi_coefs_tmp(i)*psi_coefs_tmp(i)*s2_tmp
- enddo
- s2 = s2 + S_z2_Sz
+  !$OMP END PARALLEL
+  s2 = s2+s2
+  do i=1,n
+    call get_s2(psi_keys_tmp(1,1,i),psi_keys_tmp(1,1,i),s2_tmp,N_int)
+    s2 = s2 + psi_coefs_tmp(i)*psi_coefs_tmp(i)*s2_tmp
+  enddo
+  s2 = s2 + S_z2_Sz
 end
 
 
diff --git a/src/Determinants/slater_rules.irp.f b/src/Determinants/slater_rules.irp.f
index cf3b8c1e..4cb1afff 100644
--- a/src/Determinants/slater_rules.irp.f
+++ b/src/Determinants/slater_rules.irp.f
@@ -1068,14 +1068,14 @@ double precision function diag_H_mat_elem(det_in,Nint)
   nexc(1) = 0
   nexc(2) = 0
   do i=1,Nint
-    hole(i,1)     =  xor(det_in(i,1),ref_bitmask(i,1))
-    hole(i,2)     =  xor(det_in(i,2),ref_bitmask(i,2))
+    hole(i,1)     = xor(det_in(i,1),ref_bitmask(i,1))
+    hole(i,2)     = xor(det_in(i,2),ref_bitmask(i,2))
     particle(i,1) = iand(hole(i,1),det_in(i,1))
     particle(i,2) = iand(hole(i,2),det_in(i,2))
     hole(i,1)     = iand(hole(i,1),ref_bitmask(i,1))
     hole(i,2)     = iand(hole(i,2),ref_bitmask(i,2))
-    nexc(1)      += popcnt(hole(i,1))
-    nexc(2)      += popcnt(hole(i,2))
+    nexc(1)       = nexc(1) + popcnt(hole(i,1))
+    nexc(2)       = nexc(2) + popcnt(hole(i,2))
   enddo
   
   diag_H_mat_elem = ref_bitmask_energy
@@ -1239,81 +1239,99 @@ subroutine H_u_0(v_0,u_0,H_jj,n,keys_tmp,Nint)
   
   integer                        :: shortcut(0:n+1), sort_idx(n)
   integer(bit_kind)              :: sorted(Nint,n), version(Nint,n)
+  integer(bit_kind)              :: sorted_i(Nint)
   
   
   integer                        :: sh, sh2, ni, exa, ext, org_i, org_j, endi
-!   
+  double precision               :: local_threshold
   
 
   ASSERT (Nint > 0)
   ASSERT (Nint == N_int)
   ASSERT (n>0)
-  PROVIDE ref_bitmask_energy
-  !$OMP PARALLEL DEFAULT(NONE)                                       &
-      !$OMP PRIVATE(i,hij,j,k,idx,jj,vt,ii,sh,sh2,ni,exa,ext,org_i,org_j,endi)                             &
-      !$OMP SHARED(n,H_jj,u_0,keys_tmp,Nint,v_0,davidson_threshold,sorted,shortcut,sort_idx,version,davidson_criterion_is_built)
-  allocate(idx(0:n), vt(n))
-  Vt = 0.d0
+  PROVIDE ref_bitmask_energy davidson_criterion
   v_0 = 0.d0
-  
-  !$OMP SINGLE
+
   call sort_dets_ab_v(keys_tmp, sorted, sort_idx, shortcut, version, n, Nint)
-  !$OMP END SINGLE
+  
+  !$OMP PARALLEL DEFAULT(NONE)                                       &
+      !$OMP PRIVATE(i,hij,j,k,jj,vt,ii,sh,sh2,ni,exa,ext,org_i,org_j,endi,local_threshold,sorted_i)&
+      !$OMP SHARED(n,H_jj,u_0,keys_tmp,Nint,v_0,davidson_threshold,sorted,shortcut,sort_idx,version)
+  allocate(vt(n))
+  Vt = 0.d0
   
   !$OMP DO SCHEDULE(dynamic)
   do sh=1,shortcut(0)
-  do sh2=1,sh
-    exa = 0
-    do ni=1,Nint
-      exa += popcnt(xor(version(ni,sh), version(ni,sh2)))
-    end do
-    if(exa > 2) then
-      cycle
-    end if
-    
-    do i=shortcut(sh),shortcut(sh+1)-1
-      if(sh==sh2) then
-        endi = i-1
-      else
-        endi = shortcut(sh2+1)-1
+    do sh2=1,sh
+      exa = 0
+      do ni=1,Nint
+        exa = exa + popcnt(xor(version(ni,sh), version(ni,sh2)))
+      end do
+      if(exa > 2) then
+        cycle
       end if
       
-      do j=shortcut(sh2),endi
-       ext = exa
+      do i=shortcut(sh),shortcut(sh+1)-1
+        org_i = sort_idx(i)
+        local_threshold = davidson_threshold - dabs(u_0(org_i))
+        if(sh==sh2) then
+          endi = i-1
+        else
+          endi = shortcut(sh2+1)-1
+        end if
         do ni=1,Nint
-          ext += popcnt(xor(sorted(ni,i), sorted(ni,j)))
-        end do
-        if(ext <= 4) then
-          org_i = sort_idx(i)
+          sorted_i(ni) = sorted(ni,i)
+        enddo
+        
+        do j=shortcut(sh2),endi
           org_j = sort_idx(j)
-          if ( dabs(u_0(org_j)) + dabs(u_0(org_i)) > davidson_threshold ) then
-            call i_H_j(keys_tmp(1,1,org_j),keys_tmp(1,1,org_i),Nint,hij)
-            vt (org_i) = vt (org_i) + hij*u_0(org_j)
-            vt (org_j) = vt (org_j) + hij*u_0(org_i)
+          if ( dabs(u_0(org_j)) > local_threshold ) then
+            ext = exa
+            do ni=1,Nint
+              ext = ext + popcnt(xor(sorted_i(ni), sorted(ni,j)))
+            end do
+            if(ext <= 4) then
+              call i_H_j(keys_tmp(1,1,org_j),keys_tmp(1,1,org_i),Nint,hij)
+              vt (org_i) = vt (org_i) + hij*u_0(org_j)
+              vt (org_j) = vt (org_j) + hij*u_0(org_i)
+            endif
           endif
-        endif
+        enddo
       enddo
     enddo
   enddo
-  enddo
   !$OMP END DO
   
-  !$OMP SINGLE
+  !$OMP CRITICAL
+  do i=1,n
+    v_0(i) = v_0(i) + vt(i)
+  enddo
+  !$OMP END CRITICAL
+  
+  deallocate(vt)
+  !$OMP END PARALLEL
+  
   call sort_dets_ba_v(keys_tmp, sorted, sort_idx, shortcut, version, n, Nint)
-  !$OMP END SINGLE
- 
+  
+  !$OMP PARALLEL DEFAULT(NONE)                                       &
+      !$OMP PRIVATE(i,hij,j,k,jj,vt,ii,sh,sh2,ni,exa,ext,org_i,org_j,endi,local_threshold)&
+      !$OMP SHARED(n,H_jj,u_0,keys_tmp,Nint,v_0,davidson_threshold,sorted,shortcut,sort_idx,version)
+  allocate(vt(n))
+  Vt = 0.d0
+  
   !$OMP DO SCHEDULE(dynamic)
   do sh=1,shortcut(0)
     do i=shortcut(sh),shortcut(sh+1)-1
+      local_threshold = davidson_threshold - dabs(u_0(org_i))
+      org_i = sort_idx(i)
       do j=shortcut(sh),i-1
-        ext = 0
-        do ni=1,Nint
-          ext += popcnt(xor(sorted(ni,i), sorted(ni,j)))
-        end do
-        if(ext == 4) then
-          org_i = sort_idx(i)
-          org_j = sort_idx(j)
-          if ( dabs(u_0(org_j)) + dabs(u_0(org_i)) > davidson_threshold ) then
+        org_j = sort_idx(j)
+        if ( dabs(u_0(org_j)) > local_threshold ) then
+          ext = 0
+          do ni=1,Nint
+            ext = ext + popcnt(xor(sorted(ni,i), sorted(ni,j)))
+          end do
+          if(ext == 4) then
             call i_H_j(keys_tmp(1,1,org_j),keys_tmp(1,1,org_i),Nint,hij)
             vt (org_i) = vt (org_i) + hij*u_0(org_j)
             vt (org_j) = vt (org_j) + hij*u_0(org_i)
@@ -1329,8 +1347,9 @@ subroutine H_u_0(v_0,u_0,H_jj,n,keys_tmp,Nint)
     v_0(i) = v_0(i) + vt(i)
   enddo
   !$OMP END CRITICAL
-  deallocate(idx,vt)
+  deallocate(vt)
   !$OMP END PARALLEL
+  
   do i=1,n
     v_0(i) += H_jj(i) * u_0(i)
   enddo
diff --git a/src/Determinants/spindeterminants.irp.f b/src/Determinants/spindeterminants.irp.f
index b8f1b68c..0ca6301a 100644
--- a/src/Determinants/spindeterminants.irp.f
+++ b/src/Determinants/spindeterminants.irp.f
@@ -442,13 +442,14 @@ BEGIN_PROVIDER [ double precision, psi_bilinear_matrix, (N_det_alpha_unique,N_de
   enddo
 END_PROVIDER
 
-subroutine create_wf_of_psi_bilinear_matrix
+subroutine create_wf_of_psi_bilinear_matrix(truncate)
   use bitmasks
   implicit none
   BEGIN_DOC
 ! Generate a wave function containing all possible products 
 ! of alpha and beta determinants
   END_DOC
+  logical, intent(in)            :: truncate
   integer                        :: i,j,k
   integer(bit_kind)              :: tmp_det(N_int,2)
   integer                        :: idx
@@ -488,8 +489,10 @@ subroutine create_wf_of_psi_bilinear_matrix
   norm(1) = 0.d0
   do i=1,N_det
     norm(1) += psi_average_norm_contrib_sorted(i)
-    if (norm(1) >= 0.999999d0) then
-      exit
+    if (truncate) then
+      if (norm(1) >= 0.999999d0) then
+        exit
+      endif
     endif
   enddo
   N_det = min(i,N_det)
@@ -532,7 +535,6 @@ subroutine generate_all_alpha_beta_det_products
   !$OMP END DO NOWAIT
   deallocate(tmp_det)
   !$OMP END PARALLEL
-  deallocate (tmp_det)
   call copy_H_apply_buffer_to_wf
   SOFT_TOUCH psi_det psi_coef N_det
 end
diff --git a/src/Determinants/truncate_wf.irp.f b/src/Determinants/truncate_wf.irp.f
index f867ad7e..42340c71 100644
--- a/src/Determinants/truncate_wf.irp.f
+++ b/src/Determinants/truncate_wf.irp.f
@@ -8,10 +8,10 @@ program cisd
   N_det=10000
   do i=1,N_det
     do k=1,N_int
-    psi_det(k,1,i) = psi_det_sorted(k,1,i)
-    psi_det(k,2,i) = psi_det_sorted(k,2,i)
+      psi_det(k,1,i) = psi_det_sorted(k,1,i)
+      psi_det(k,2,i) = psi_det_sorted(k,2,i)
     enddo
-    psi_coef(k,:)  = psi_coef_sorted(k,:)
+    psi_coef(i,:)  = psi_coef_sorted(i,:)
   enddo
   TOUCH psi_det psi_coef psi_det_sorted psi_coef_sorted psi_average_norm_contrib_sorted N_det
   call save_wavefunction