Please do note: these files will NOT work properly with the latest versions of 
SPFIT and SPCAT. Some transitions will be rejected or will display large residuals. 
An as of now unknown error shifts some HFS components by substantial or large amounts. 
These levels have a calculated mixing coefficient of exactly zero. Consequntly, these 
transitions will have zero intensity in a catalog file, i.e., they will NOT show up. 

These errors have not occured with versions from 2006; the latest version is from July 2007.


There are two sets of files, CH3O.* and sym.*; 

CH3O.* are files, in which A and B are fit using the asymmetric rotor codes for A and B; 
C needs to be included as well, and it needs to be constrained to B, 
this is enforced by the minus sign in front of the code for C. 
These files may be viewed by some as favorite ones; 
they have the advantage that the values are comparable directly to previous ones. 
See also sym.par for the difference!

The sym.* files are actually the preferred ones with thy symmetric rotor codes 
for A - B and for B. 

Methoxy is a doublet radical in a degenerate E state, 
hence the two option lines in the parameter file in which EWT 100 and 200 
define the two l-doubled states.

IAX = -6 indicates that the last three spins are coupled together to I_tot. 

The first of the four successive 2 for the spins is for the electron spin; 
the "-" in the first option line signals to use symmetric rotor quanta. 


The energy code E is required to put the lowest allowed rovibronic level 
to the energy of zero!


The next parameters are the rotational and centrifugal distortion parameters. 


alpha (code 630000; sometimes also called epsilon) is also a distortion parameter 
connecting levels with DeltaK = 3. 


The code 200000 represents the regular Coriolis interaction in a 
degenerate vibrational state of a symmetric top. 
In the case of l = +-1, it represents -2AZeta, here called -2AZeta_t. 
(In the case of l = -+2, it represents 4AZeta; also signaled by EWT 100 and 200. 

The following four parameter are distortion corrections to -2AZeta. 


h1 and h2 (plus h4, but this was omitted in the present fit) are lambda-doubling 
parameters, here with two and one distortion correction, respectively. 


The following 9 parameters are fine structure parameters. 

10200000 represents aZeta_ed, an electron spin Coriolis parameter. 
One distortion correction was employed. 

eps_aa, eps_bb, and eps_cc are the electron spin-rotation parameters, 
treated as were the rotational parameters; 
see also sym.par for the difference!

eps1 and eps2 are electron spin lambda-doubling parameters. 

Two electron spin-distortion parameters were used, D(S)NK and D(S)N. 

The last 7 parameters are hyperfine structure parameters; 
aL is obviously a hyperfine Coriolis parameter; 
and we have two sets of electron spin-nuclear spin coupling parameters. 

Nuclear spin-rotation and nuclear spin-nuclear spin coupling patrameters 
are obviously also allowed, but they were not determined well enough 
and omitted from the final fits -- as were plenty of other parameters. 
See the paper for more details.