diff --git a/src/Hartree_Fock/diagonalize_fock.irp.f b/src/Hartree_Fock/diagonalize_fock.irp.f
index d2e6d538..9a396055 100644
--- a/src/Hartree_Fock/diagonalize_fock.irp.f
+++ b/src/Hartree_Fock/diagonalize_fock.irp.f
@@ -1,4 +1,4 @@
- BEGIN_PROVIDER [ double precision, diagonal_Fock_matrix_mo, (mo_tot_num) ]
+ BEGIN_PROVIDER [ double precision, diagonal_Fock_matrix_mo, (ao_num) ]
 &BEGIN_PROVIDER [ double precision, eigenvectors_Fock_matrix_mo, (ao_num_align,mo_tot_num) ]
    implicit none
    BEGIN_DOC
@@ -26,7 +26,7 @@
 
    lwork = -1
    liwork = -1
-   call dsygvd(1,'v','u',mo_tot_num,F,size(F,1),S,size(S,1),&
+   call dsygvd(1,'v','u',ao_num,F,size(F,1),S,size(S,1),&
      diagonal_Fock_matrix_mo, work, lwork, iwork, liwork, info)
 
    if (info /= 0) then
@@ -38,14 +38,14 @@
    deallocate(work,iwork)
    allocate(work(lwork), iwork(liwork) )
 
-   call dsygvd(1,'v','u',mo_tot_num,F,size(F,1),S,size(S,1),&
+   call dsygvd(1,'v','u',ao_num,F,size(F,1),S,size(S,1),&
      diagonal_Fock_matrix_mo, work, lwork, iwork, liwork, info)
 
    if (info /= 0) then
      print *,  irp_here//' failed'
      stop 1
    endif
-   do j=1,ao_num
+   do j=1,mo_tot_num
      do i=1,ao_num
        eigenvectors_Fock_matrix_mo(i,j) = F(i,j)
      enddo