Loomis-Wood diagram

Loomis-Wood diagram

[′lü·məs ′wu̇d ‚dī·ə‚gram]
(spectroscopy)
A graph used to assign lines in a molecular spectrum to the various branches of rotational bands when these branches overlap, in which the difference between observed wave numbers and wave numbers extrapolated from a few lines that apparently belong to one branch are plotted against arbitrary running numbers for that branch.