diff --git a/plugins/core_integrals/.gitignore b/plugins/core_integrals/.gitignore
new file mode 100644
index 00000000..7ac9fbf6
--- /dev/null
+++ b/plugins/core_integrals/.gitignore
@@ -0,0 +1,5 @@
+IRPF90_temp/
+IRPF90_man/
+irpf90.make
+irpf90_entities
+tags
\ No newline at end of file
diff --git a/plugins/core_integrals/AO_Basis b/plugins/core_integrals/AO_Basis
new file mode 120000
index 00000000..bee933ae
--- /dev/null
+++ b/plugins/core_integrals/AO_Basis
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/AO_Basis
\ No newline at end of file
diff --git a/plugins/core_integrals/Bitmask b/plugins/core_integrals/Bitmask
new file mode 120000
index 00000000..2f693e1c
--- /dev/null
+++ b/plugins/core_integrals/Bitmask
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Bitmask
\ No newline at end of file
diff --git a/plugins/core_integrals/Electrons b/plugins/core_integrals/Electrons
new file mode 120000
index 00000000..c29d5ab7
--- /dev/null
+++ b/plugins/core_integrals/Electrons
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Electrons
\ No newline at end of file
diff --git a/plugins/core_integrals/Ezfio_files b/plugins/core_integrals/Ezfio_files
new file mode 120000
index 00000000..07172795
--- /dev/null
+++ b/plugins/core_integrals/Ezfio_files
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Ezfio_files
\ No newline at end of file
diff --git a/plugins/core_integrals/Integrals_Bielec b/plugins/core_integrals/Integrals_Bielec
new file mode 120000
index 00000000..fe90d314
--- /dev/null
+++ b/plugins/core_integrals/Integrals_Bielec
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Integrals_Bielec
\ No newline at end of file
diff --git a/plugins/core_integrals/Integrals_Monoelec b/plugins/core_integrals/Integrals_Monoelec
new file mode 120000
index 00000000..ef392ff9
--- /dev/null
+++ b/plugins/core_integrals/Integrals_Monoelec
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Integrals_Monoelec
\ No newline at end of file
diff --git a/plugins/core_integrals/MO_Basis b/plugins/core_integrals/MO_Basis
new file mode 120000
index 00000000..55d01a67
--- /dev/null
+++ b/plugins/core_integrals/MO_Basis
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/MO_Basis
\ No newline at end of file
diff --git a/plugins/core_integrals/Makefile b/plugins/core_integrals/Makefile
new file mode 100644
index 00000000..bfcd2493
--- /dev/null
+++ b/plugins/core_integrals/Makefile
@@ -0,0 +1,16 @@
+IRPF90 = irpf90  #-a -d
+FC     = gfortran
+FCFLAGS= -O2 -ffree-line-length-none -I .
+NINJA  = ninja
+AR     = ar
+RANLIB = ranlib
+
+SRC=
+OBJ=
+LIB=
+
+include irpf90.make
+export
+
+irpf90.make: $(filter-out IRPF90_temp/%, $(wildcard */*.irp.f)) $(wildcard *.irp.f) $(wildcard *.inc.f) Makefile 
+	$(IRPF90)
diff --git a/plugins/core_integrals/NEEDED_CHILDREN_MODULES b/plugins/core_integrals/NEEDED_CHILDREN_MODULES
new file mode 100644
index 00000000..6a4d0040
--- /dev/null
+++ b/plugins/core_integrals/NEEDED_CHILDREN_MODULES
@@ -0,0 +1 @@
+Integrals_Monoelec Integrals_Bielec Bitmask
diff --git a/plugins/core_integrals/Nuclei b/plugins/core_integrals/Nuclei
new file mode 120000
index 00000000..a21d375b
--- /dev/null
+++ b/plugins/core_integrals/Nuclei
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Nuclei
\ No newline at end of file
diff --git a/plugins/core_integrals/Pseudo b/plugins/core_integrals/Pseudo
new file mode 120000
index 00000000..69623db7
--- /dev/null
+++ b/plugins/core_integrals/Pseudo
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Pseudo
\ No newline at end of file
diff --git a/plugins/core_integrals/README.rst b/plugins/core_integrals/README.rst
new file mode 100644
index 00000000..589e0a00
--- /dev/null
+++ b/plugins/core_integrals/README.rst
@@ -0,0 +1,12 @@
+==============
+core_integrals
+==============
+
+Needed Modules
+==============
+.. Do not edit this section It was auto-generated
+.. by the `update_README.py` script.
+Documentation
+=============
+.. Do not edit this section It was auto-generated
+.. by the `update_README.py` script.
diff --git a/plugins/core_integrals/Utils b/plugins/core_integrals/Utils
new file mode 120000
index 00000000..22bcf3f5
--- /dev/null
+++ b/plugins/core_integrals/Utils
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/Utils
\ No newline at end of file
diff --git a/plugins/core_integrals/ZMQ b/plugins/core_integrals/ZMQ
new file mode 120000
index 00000000..cbbfca4c
--- /dev/null
+++ b/plugins/core_integrals/ZMQ
@@ -0,0 +1 @@
+/home/giner/qp_bis/quantum_package/src/ZMQ
\ No newline at end of file
diff --git a/plugins/core_integrals/core_integrals.main b/plugins/core_integrals/core_integrals.main
new file mode 100755
index 00000000..de1348c4
Binary files /dev/null and b/plugins/core_integrals/core_integrals.main differ
diff --git a/plugins/core_integrals/core_integrals.main.irp.f b/plugins/core_integrals/core_integrals.main.irp.f
new file mode 100644
index 00000000..f5e9fd1b
--- /dev/null
+++ b/plugins/core_integrals/core_integrals.main.irp.f
@@ -0,0 +1,7 @@
+program core_integrals
+  implicit none
+  BEGIN_DOC
+! TODO
+  END_DOC
+  print*,'core energy = ',core_energy 
+end
diff --git a/plugins/core_integrals/core_quantities.irp.f b/plugins/core_integrals/core_quantities.irp.f
new file mode 100644
index 00000000..ac547d2f
--- /dev/null
+++ b/plugins/core_integrals/core_quantities.irp.f
@@ -0,0 +1,32 @@
+BEGIN_PROVIDER [double precision, core_energy]
+ implicit none
+ integer :: i,j,k,l
+ core_energy = 0.d0
+ do i = 1, n_core_orb
+  j = list_core(i)
+  core_energy += 2.d0 * mo_mono_elec_integral(j,j) + mo_bielec_integral_jj(j,j)
+  do k = i+1, n_core_orb
+   l = list_core(k)
+   core_energy += 2.d0 * (2.d0 * mo_bielec_integral_jj(j,l) - mo_bielec_integral_jj_exchange(j,l))
+  enddo
+ enddo
+ core_energy += nuclear_repulsion
+
+END_PROVIDER
+
+BEGIN_PROVIDER [double precision, core_fock_operator, (mo_tot_num,mo_tot_num)]
+ implicit none
+ integer :: i,j,k,l,m,n
+ double precision :: get_mo_bielec_integral
+ core_fock_operator = 0.d0
+ do i = 1, n_act_orb
+  j = list_act(i)
+  do k = 1, n_act_orb
+   l = list_act(k)
+   do m = 1, n_core_orb
+    n = list_core(m)
+    core_fock_operator(j,l) += 2.d0 * get_mo_bielec_integral(j,n,l,n,mo_integrals_map) - get_mo_bielec_integral(j,n,n,l,mo_integrals_map)
+   enddo
+  enddo
+ enddo
+END_PROVIDER