diff --git a/config/ifort_xHost.cfg b/config/ifort_xHost.cfg
new file mode 100644
index 00000000..5d952e54
--- /dev/null
+++ b/config/ifort_xHost.cfg
@@ -0,0 +1,63 @@
+# Common flags
+##############
+#
+# -mkl=[parallel|sequential] : Use the MKL library
+# --ninja                 : Allow the utilisation of ninja. It is mandatory !
+# --align=32                 : Align all provided arrays on a 32-byte boundary
+#
+[COMMON]
+FC           : ifort -fpic 
+LAPACK_LIB   : -mkl=parallel
+IRPF90       : irpf90
+IRPF90_FLAGS : --ninja --align=64
+
+# Global options
+################
+#
+# 1 : Activate
+# 0 : Deactivate
+#
+[OPTION]
+MODE    : OPT        ; [ OPT | PROFILE | DEBUG ] : Chooses the section below
+CACHE   : 0          ; Enable cache_compile.py
+OPENMP  : 1          ; Append OpenMP flags
+
+# Optimization flags
+####################
+#
+# -xHost                     : Compile a binary optimized for the current architecture
+# -O2                        : O3 not better than O2.
+# -ip                        : Inter-procedural optimizations
+# -ftz                       : Flushes denormal results to zero
+#
+[OPT]
+FC       : -traceback
+FCFLAGS  : -xHost -O2 -ip -ftz -g
+
+# Profiling flags
+#################
+#
+[PROFILE]
+FC       : -p -g
+FCFLAGS  : -xSSE4.2 -O2 -ip -ftz
+
+# Debugging flags
+#################
+#
+# -traceback   : Activate backtrace on runtime
+# -fpe0        : All floating point exaceptions
+# -C           : Checks uninitialized variables,  array subscripts, etc...
+# -g           : Extra debugging information
+# -xSSE2       : Valgrind needs a very simple x86 executable
+#
+[DEBUG]
+FC      : -g -traceback
+FCFLAGS : -xSSE2 -C -fpe0  -implicitnone
+
+# OpenMP flags
+#################
+#
+[OPENMP]
+FC           : -qopenmp
+IRPF90_FLAGS : --openmp
+
diff --git a/src/tools/print_energy.irp.f b/src/tools/print_energy.irp.f
index f78dffc8..53fea44e 100644
--- a/src/tools/print_energy.irp.f
+++ b/src/tools/print_energy.irp.f
@@ -14,6 +14,9 @@ end
 
 subroutine run
  implicit none
+ BEGIN_DOC
+! E = \sum_{ij} c_i c_j H_{ij}  / \sum{i} c_i^2
+ END_DOC
  integer :: i,j
  double precision :: i_H_psi_array(N_states)
  double precision :: E(N_states)