diff --git a/ChangeLog b/ChangeLog
index d80484121c5ba1818dea94c194b80017a14e4b36..c8847ae750ea3fbec5b8c20ba3be604d8364f5bc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2013-10-12 Jana Mendrok <jana.mendrok@ltu.se>
 
+	* ARTS-XML-DATA-2-1-63
+
+	* spectroscopy/Perrin/ARTSCAT-4_Col29_Conventions.txt:
+	Updated O2 convention according to new info and data from Agnes (see
+	previous commit).
+
+2013-10-25 Jana Mendrok <jana.mendrok@ltu.se>
+
 	* ARTS-XML-DATA-2-1-62
 
 	* spectroscopy/Perrin/O2.xml.gz: New O2 line fiel from Agnes with
diff --git a/spectroscopy/Perrin/ARTSCAT-4_Col29_Conventions.txt b/spectroscopy/Perrin/ARTSCAT-4_Col29_Conventions.txt
index c381d3c08828ed29e2878a2b5cb66eab20ec4907..a122194182d5057c153e47a5b8f6ef253e61f800 100644
--- a/spectroscopy/Perrin/ARTSCAT-4_Col29_Conventions.txt
+++ b/spectroscopy/Perrin/ARTSCAT-4_Col29_Conventions.txt
@@ -278,19 +278,52 @@ $$$$$$$$$$$$$$$$$$$$$
 
 Molecular oxygen
 
-G= (2xN+1)
-                                                           upper         lower
-                                  g_up    g_low     vib   N   J   F    N   J   F 
-@   O2-67             9000.00     62.0     65.0     000   32  32  31   32  32  30
-@   O2-67            23500.00     62.0     67.0     000   33  33  31   33  33  32
-@   O2-68            40100.00    121.0    121.0     000   60           60        
-@   O2-68            40500.00    119.0    119.0     000   59           59        
-@   O2-66            40800.00    119.0    119.0     000   59           59        
-@   O2-66            40800.00    119.0    119.0     001   59           59        
-@   O2-68            40900.00    117.0    117.0     000   58           58        
-@   O2-68            41400.00    115.0    115.0     000   57           57        
-@   O2-66            41700.00    115.0    115.0     001   57           57        
-@   O2-66            41700.00    115.0    115.0     000   57           57        
+===>  For O16-O16  and O16-O18, 
+We just have a spin structure. So the J value can take 3 values which are:  J=N,N-1 and N+1  
+Condition:  J  cannot be negative (of course)
+we do not have to deal with an hyperfine stucture
+So, there is no F_upper  or F_lower rotational quantum numbers.
+ (In fact, F_upper=J_upper and F_lower=J_lower)
+
+==========================================================================
+
+===>  For O16-O17, we have to deal with I(O17)=5.2. 
+The J value can take 3 values which are:  J=N,N-1 and N+1  
+Condition:  J  cannot be negative (of course)
+In addition, one has to deal with the hyperfine structure. (I(O17)=5/2
+For this reason, F_upper (and F_lower) can take 6 different values, which are:
+ F_upper= J_upper-5/2,  J_upper-3/2, J_upper-1/2, J_upper+1/2, J_upper+3/2 and J_upper+5/2
+Condition: one should ALWAYS have   J  and F cannot be negative (of course)
+
+ATTENTION: Here, I have coded   F+.5 (as in the JPL catalog)
+
+
+
+=================================================================
+
+G_upper= (2*F_upper+1)  for O16-O17
+
+G_upper= (2*J_upper+1)  for O16-O16  and O16-O18
+
+===================================================================
+
+Vib:  VIB=000  for transitions within the ground state
+      Vib=001  for transitions withing the v=1 (first excited) vibrational state
+
+                                                                                                                                  UPPER        LOWER
+                sigma                                                           G_sup   G_inf                              Vib
+                                                                                                                                  N   J  F+.5  N   J  F+.5
+@   O2-67      693475.3277E+06 0.18006E-30 296  0.36837841351E-21 0.000E+00      8.0     10.0  16726.000  ----   0.000E+00 000    5   6   4    3   3   5     F'=3.5   F"=4.5   G_upper=2*3.5+1   G_lower=2*4.5+1
+@   O2-67      693489.8026E+06 0.28171E-29 296  0.36836848128E-21 0.000E+00      8.0      8.0  16726.000  ----   0.000E+00 000    5   6   4    3   3   4     F'=3.5   F"=3.5   G_upper=2*3.5+1   G_lower=2*4.5+1
+@   O2-67      693500.5568E+06 0.70179E-29 296  0.36836252194E-21 0.000E+00      8.0      6.0  16726.000  ----   0.000E+00 000    5   6   4    3   3   3
+@   O2-66      706775.4249E+06 0.99085E-22 296  0.31277392416E-19 0.000E+00      9.0      7.0  16726.000  ----   0.000E+00 001    5   4        3   3           G_upper=2*4+1   G_lower=2*3+1  
+@   O2-66      715392.9800E+06 0.19038E-18 296  0.36425852508E-21 0.000E+00      9.0      7.0  16726.000  ----   0.000E+00 000    5   4        3   3
+@   O2-68      731186.6780E+06 0.57846E-18 296  0.32073351285E-21 0.000E+00      9.0      9.0  16726.000  ----   0.000E+00 000    5   4        3   4
+@   O2-67      750637.9001E+06 0.31905E-19 296  0.32975594932E-21 0.000E+00      4.0      4.0  16726.000  ----   0.000E+00 000    5   4   2    3   4   2
+@   O2-67      750693.0711E+06 0.10641E-19 296  0.32972019329E-21 0.000E+00      4.0      6.0  16726.000  ----   0.000E+00 000    5   4   2    3   4   3
+@   O2-67      750696.2538E+06 0.10641E-19 296  0.32975594932E-21 0.000E+00      6.0      4.0  16726.000  ----   0.000E+00 000    5   4   3    3   4   2
+@   O2-67      750751.4248E+06 0.36455E-19 296  0.32972019329E-21 0.000E+00      6.0      6.0  16726.000  ----   0.000E+00 000    5   4   3    3   4   3
+@   O2-67      750828.3467E+06 0.16725E-19 296  0.32966854571E-21 0.000E+00      6.0      8.0  16726.000  ----   0.000E+00 000    5   4   3    3   4   4