diff --git a/ener_lib.cif b/ener_lib.cif
index 0b157c373..dea7c7f28 100644
--- a/ener_lib.cif
+++ b/ener_lib.cif
@@ -52,11 +52,16 @@ data_energy
 #ATOMTYPE NS   = without hydrogen ( triple bond ) = NSP
 #ATOMTYPE NS1  = connected to 1 hydrogen = NSP1
 #HEADER        N Nitrogen SP2
-#ATOMTYPE NC1  = connected to 1 hyd. in a charged group ( NE of ARG )
-#ATOMTYPE NC2  = connected to 2 hyd. in a charged group ( NH2 of ARG )
+## N with three bonds
 #ATOMTYPE NH0  = connected to 0 hydrogen
 #ATOMTYPE NH1  = connected to 1 hydrogen ( N of main chain )
 #ATOMTYPE NH2  = connected to 2 hydrogen ( NE2 of GLU )
+## N with two bonds
+#ATOMTYPE N20  = connected to 0 hydrogen
+#ATOMTYPE N21  = connected to 1 hydrogen
+## OBSOLETE
+#ATOMTYPE NC1  = connected to 1 hyd. in a charged group ( NE of ARG )
+#ATOMTYPE NC2  = connected to 2 hyd. in a charged group ( NH2 of ARG )
 #ATOMTYPE NPA  = without hydrogen ( NA and NC of HEME )
 #ATOMTYPE NPB  = without hydrogen ( NB and ND of HEME )
 #ATOMTYPE NRD5 = without hydrogen but with electronic doublet in 5 atoms ring
@@ -64,7 +69,10 @@ data_energy
 #ATOMTYPE NR15 = connected to 1 hyd. in 5 atoms ring ( ND1 of HIS )
 #ATOMTYPE NR16 = connected to 1 hyd. in 6  atoms ring 
 #ATOMTYPE NR5  = connected to 3 non-hydrogen atoms in 5 atoms ring
+#ATOMTYPE NR55 = between two atoms in 5-5 rings
+#ATOMTYPE NR56 = between two atoms in 5-6 rings
 #ATOMTYPE NR6  = connected to 3 non-hydrogen atoms in 6 atoms ring
+#ATOMTYPE NR66 = between two atoms in 6-6 rings
 #HEADER        N Nitrogen SP3
 # N with four bonds
 #ATOMTYPE N    = without hydrogen
@@ -165,13 +173,15 @@ _lib_atom.sp
  NSP     14.00670  A     1.550     1.600    1.32   N   3  1
  NS1     14.00670  D     1.550     1.600    1.32   N   3  1
  NSP1    14.00670  D     1.550     1.600    1.32   N   3  1
- N       14.00670  B     1.550     1.600    1.32   N   3  2
+ N       14.00670  N     1.550     1.600    1.32   N   3  2
  NC1     14.00670  D     1.550     1.600    1.32   N   3  2
  NH0     14.00670  N     1.550     1.600    1.32   N   3  2
  NH1     14.00670  D     1.550     1.600    1.32   N   3  2
  NC2     14.00670  D     1.550     1.600    1.32   N   3  2
  NH2     14.00670  D     1.550     1.600    1.32   N   3  2
  NC3     14.00670  D     1.550     1.600    1.32   N   3  2
+ N20     14.00670  A     1.550     1.600    1.32   N   3  2
+ N21     14.00670  B     1.550     1.600    1.32   N   3  2
  NT      14.00670  N     1.550     1.600    1.32   N   3  3
  NT1     14.00670  D     1.550     1.600    1.32   N   3  3
  NT2     14.00670  D     1.550     1.600    1.32   N   3  3
@@ -186,8 +196,8 @@ _lib_atom.sp
  NR5     14.00670  A     1.550     1.600    1.32   N   3  2
  NR15    14.00670  D     1.550     1.600    1.32   N   3  2
  NRD5    14.00670  A     1.550     1.600    1.32   N   3  2
- NR56    14.00670  A     1.550     1.600    1.32   N   3  2
- NR55    14.00670  A     1.550     1.600    1.32   N   3  2
+ NR56    14.00670  N     1.550     1.600    1.32   N   3  2
+ NR55    14.00670  N     1.550     1.600    1.32   N   3  2
  NR6     14.00670  A     1.550     1.600    1.32   N   3  2
  NR66    14.00670  N     1.550     1.600    1.32   N   3  2
  NR16    14.00670  D     1.550     1.600    1.32   N   3  2