Updated zeeman_constants.xml format in ARTS.

git-svn-id: https://radiativetransfer.org/svn/rt/arts-xml-data/trunk@9848 aaf1aab0-4228-0410-ad68-8dceda47f409

ChangeLog

+2016-05-20  Richard Larsson  <ric.larsson@gmail.com>
+
+	* ARTS-XML-DATA-2-3-22
+	
+	* spectroscopy/QuantumConstants/*:  Updated for change that allows
+	Hund case a to work as expected.
+
 2016-01-27  Oliver Lemke  <olemke@core-dump.info>
 
 	* ARTS-XML-DATA-2-3-21

spectroscopy/QuantumConstants/README

 Format of zeeman_constants.xml:
 
-@ Isotope GS Spin Hund_case
+@ Isotope GS Lambda Spin Hund_case
 
 where GS is a constant for the molecule that calculates the effective g-value,
-Spin is a molecular constant, and Hund_case tells the program to estimate the
-calculations with a specific Hund case.
+Lambda is the ground state number,  Spin is the spin, and Hund_case tells the
+program to estimate the calculations with a specific Hund case.
+Note, for example, that O2 ground state is Sigma_3, so Lambda is 0 and S is 1, NO ground
+state is Pi_2 so Lambda is 1 and S is 1/2.
 
 The Zeeman split is calculated with changes in energy levels. Essentially, 
 dE = g M C_Z,
@@ -26,7 +28,8 @@ Hund case b is number "1".
 Assuming the electron is free, then GS = 2.0023193043622.
 We used this assumption when we had no other data for GS. However, we do not
 know how well this assumption holds for the respective molecules. Currently,
-this regards NO2 and HO2.
+this regards NO2 and HO2, though these are only included for reference and will
+not run.
 
 The GS values for O2, NO, OH, ClO, and SO are from 
 

spectroscopy/QuantumConstants/zeeman_constants.xml

 <?xml version="1.0"?>
 <arts format="ascii" version="1">
-<SpeciesAuxData version="1" nelem="16" nparam="3">
-@ O2-66 2.002064 1 1
-@ O2-68 2.002064 1 1
-@ O2-67 2.002064 1 1
-@ NO-46 2.00071 0.5 0
-@ NO-56 2.00071 0.5 0
-@ NO-48 2.00071 0.5 0
-@ OH-61 2.00089 0.5 0
-@ OH-81 2.00089 0.5 0
-@ OH-62 2.00089 0.5 0
-@ ClO-56 2.00072 0.5 0
-@ ClO-76 2.00072 0.5 0
-@ SO-26 2.002106 1 1
-@ SO-46 2.002106 1 1
-@ SO-28 2.002106 1 1
-@ NO2-646 2.0023193043622 0.5 1
-@ HO2-166 2.0023193043622 0.5 1
+<SpeciesAuxData version="1" nelem="16" nparam="4">
+@ O2-66 2.002064 0 1 1
+@ O2-68 2.002064 0 1 1
+@ O2-67 2.002064 0 1 1
+@ NO-46 2.00071 1 0.5 0
+@ NO-56 2.00071 1 0.5 0
+@ NO-48 2.00071 1 0.5 0
+@ OH-61 2.00089 1 0.5 0
+@ OH-81 2.00089 1 0.5 0
+@ OH-62 2.00089 1 0.5 0
+@ ClO-56 2.00072 1 0.5 0
+@ ClO-76 2.00072 1 0.5 0
+@ SO-26 2.002106 0 1 1
+@ SO-46 2.002106 0 1 1
+@ SO-28 2.002106 0 1 1
+@ NO2-646 2.0023193043622 -1 0.5 1
+@ HO2-166 2.0023193043622 -1 0.5 1
 </SpeciesAuxData>
 </arts>