Some Strategies for Rotational Line Assignments

The information required to eliminate the indeterminacy in absolute numbering of the R and P branch lines represented by the Fortrat equation can be obtained in a variety of ways  

Simultaneous analysis of two bands that share a common upper or lower electronic-vibrational level. 

A Loomis-Wood rotational branch-picking pattern recognition scheme. 

A spectral cross-correlation pattern recognition scheme. 

The way least likely to succeed is blind spectral simulation, which is the method most non-spectroscopists would normally try first. 

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