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ExoMol molecular line lists: IX The spectrum of AlO
MRNAS 2015

A.T. Patrascu, S. N. Yurchenko and J. Tennyson 

Accurate line lists are calculated for aluminium monoxide covering the pure
rotation, rotation-vibration and electronic (B - X blue-green and A - X
infrared bands) spectrum.  Line lists are presented for the four isotopologues
of AlO. These line lists are suitable for high temperatures (up to 8000 K)
including those relevant to exoplanetary atmospheres and cool stars. A
combination of empirical and ab initio methods is used: the potential energy
curves were previously determined to high accuracy by fitting to extensive data
from analysis of laboratory spectra; a high quality ab initio dipole moment
curve is calculated using quadruple zeta basis set and the multi-reference
configuration interaction (MRCI) method. Partition functions plus full line
lists of transitions are made available in an electronic form as supplementary
data to this article and at www.exomol.com.


Description:

The data for each isotopologue are in two parts. The first, .states contains a
list of rovibronic states. Each state is labelled with the total angular
momentum, state degeneracy, total parity, vibrational quantum number,
projection of the electronic, spin and total angular momenta. Each state has a
unique number, which is the number of the row in which it appears in the file.
This number is the means by which the state is related to the second part of
the data system, the transitions files.

The transition files contain three columns: the reference number in the energy
file of the upper state; that of the lower state; and the Einstein A
coefficient of the transition.

Partition functions for each isotopologue from 10 - 9000 K in steps of 10 K are 
also provided in .pf files and consist of two columns (T/K followed by Q). 

A sample programme to generate synthetic spectra from the ExoMol format line
lists can be obtained at www.exomol.com.

File Summary:
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 FileName          Explanations
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ATP__README.txt                            This file
26Al-16O__ATP.states                    Labelled rovibronic states for Al(26)O(16)
27Al-17O__ATP.states                    Labelled rovibronic states for Al(27)O(16)
27Al-17O__ATP.states                    Labelled rovibronic states for Al(27)O(17)
27Al-18O__ATP.states                    Labelled rovibronic states for Al(27)O(18)
26Al-16O__ATP.trans                     Transition file for Al(26)O(16)
27Al-17O__ATP.trans                     Transition file for Al(27)O(16)
27Al-17O__ATP.trans                     Transition file for Al(27)O(17)
27Al-18O__ATP.trans                     Transition file for Al(27)O(18)
26Al-16O__ATP.pf                        Partition Function for Al(26)O(16)
27Al-17O__ATP.pf                        Partition Function for Al(27)O(16)
27Al-17O__ATP.pf                        Partition Function for Al(27)O(17)
27Al-18O__ATP.pf                        Partition Function for Al(27)O(18)
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Byte-by-byte description of files .trans
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  Bytes Format Units   Label  Explanations
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  1- 12 i12     ---     N'    Upper state ID
 14- 25 i12     ---     N"    Lower state ID
 27- 36 e10.4   s-1     A     Einstein A-coefficient of the transition
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Byte-by-byte description of files .states
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  Bytes Format Units   Label  Explanations
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   1- 12  i12   ---   N        State ID, non-negative integer index
  14- 25  i12   cm-1  E        State energy term value in cm-1
  27- 32  i6    ---   g        Total state degeneracy
  34- 40  f7.1  ---   J        [0/39] J-quantum number J$ is the total angular
                                      momentum excluding nuclear spin
  42- 42  a1    ---   +/-      Total parity
  44- 44  a1    ---   e/f      Rotationless-parity
  46- 53  a10   ---   State    Notation of the electronic state
  57- 59  i3    ---   v        State vibrational quantum number
  62- 62  i1    ---  |Lambda|  Absolute  value of projection of electonic
                               angular momentum
  64- 70  f7.1  ---  |\Sigma|  Absolute value of projection
                               of the electronic spin
  72- 78  f7.1  ---  |\Omega|  Absolute value of projection of the total
                               angular momentum
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Contacts:
   S.N. Yurchenko, s.yurchenko@ucl.ac.uk
   J. Tennyson,  j.tennyson@ucl.ac.uk
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