Exomol molecular line lists 6: A high temperature line list for Phosphorus Nitride

Leo Yorke, Sergei N. Yurchenko,  Lorenzo Lodi and Jonathan Tennyson
MNRAS (2014)
===============================================================================

Abstract: 

Accurate rotational-vibrational line lists for two isitopologues of PN in their ground 
electronic states are computed.  The line lists are produced using an empirical potential 
energy curve obtained by fitting to the experimental transition frequencies available in 
the literature in conjunction with an accurate, high level ab initio dipole moment curve. 
In these calculations the programs DPotFit and LEVEL 8.0 were used. The new line lists 
reproduce the experimental wavenumbers with a root-mean-square error of 0.004 cm-1. The 
line lists cover the frequency range 0-51000 cm-1, contain almost 700000 lines each and 
extend up to a maximum vibrational level of v=66 and a maximum rotational level of J=357. 
They should be applicable for a large range of temperature up to, at least, 5000 K. These 
new line lists are used to simulate spectra for PN at a range of temperatures and are 
deposited in the Strasbourg data centre. This work is part of the ExoMol project [Mon. 
Not. R. Astron. Soc., 425, 21 (2012).]. 


Description: 

The data are in two parts: .states contain lists of rovibrational states of PN. Each 
state is labelled with the total angular momentum J and the vibrational quantum number v 
and represented by a unique number, which is the number of the row in which it appears in 
the .states file.  This number is the means by which the state is related to the second 
part of the data system, the transitions files. The total degeneracy is also given to 
facilitate the intensity calculations.  

The transition files .trans contain transitions given by three columns: the reference 
number in the energy file of the upper state for the isotopologue in question; that of 
the lower state; and the Einstein A coefficient of the transition. The transitions 
ordered by increasing frequency. 

There is a Fortran 90 programme, spectrum_exomol.f90 which may be used to generate 
synthetic spectra (see spectrum_exomol.txt for details). Using this, it is possible to 
generate absorption or emission spectra in either 'stick' form or else cross-sections 
convoluted with a gaussian with the half-width at half maximum being specified by the 
user, or with a the temperature-dependent doppler half-width. Sample input files with 
spectrum_exomol.f90 are supplied. 

File Summary:
ReadMe.dat                      This file
31P-14N__YYLT_T300_pf.inp                Illustration of 'partfunc' input file 
31P-14N__YYLT_T300_stick.inp             Illustration of 'stick' input file    
31P-14N__YYLT_doppl.inp             Illustration of 'doppl' input file    
31P-14N__YYLT_gauss.inp             Illustration of 'gauss' input file    
31P-14N__YYLT_bin.inp               Illustration of 'bin' input file    
31P-14N__YYLT.trans                      Frequency-ordered transitions for P14N
31P-15N__YYLT.trans                      Frequency-ordered transitions for P15N
31P-14N__YYLT.states                     Labelled rovibrational states of P14N
31P-15N__YYLT.states                     Labelled rovibrational states of P15N
31P-14N__YYLT.dat                       Partition function for P14N
31P-15N__YYLT.dat                       Partition function for P15N
31P-14N__YYLT_level.inp                    Level8.0 input file used to produce P14N line list. 
PN_PEC-A_and_PEC-S.xls             Excel spreadsheet containing PEC-A, PEC-S and the DMC.