diff --git a/src/GW/exchange_matrix_MO_basis.f90 b/src/GW/exchange_matrix_MO_basis.f90
deleted file mode 100644
index 5cb13b1..0000000
--- a/src/GW/exchange_matrix_MO_basis.f90
+++ /dev/null
@@ -1,26 +0,0 @@
-subroutine exchange_matrix_MO_basis(nBas,c,P,G,K)
-
-! Compute exchange matrix in the MO basis
-
-  implicit none
-  include 'parameters.h'
-
-! Input variables
-
-  integer,intent(in)            :: nBas
-  double precision,intent(in)   :: c(nBas,nBas),P(nBas,nBas)
-  double precision,intent(in)   :: G(nBas,nBas,nBas,nBas)
-
-! Output variables
-
-  double precision,intent(out)  :: K(nBas,nBas)
-
-! Compute Hartree Hamiltonian in the AO basis
-
-  call exchange_matrix_AO_basis(nBas,P,G,K)
-
-! Transform Coulomb matrix in the MO basis 
-
-  K = matmul(transpose(c),matmul(K,c))
-
-end subroutine exchange_matrix_MO_basis