Knowledge Bank

$l$-doublet separations in nine $\pi -\pi$ bands of $N2O$ have been measured in the region 1.4-2.4 $\mu$ with a high resolution spectrometer. The data indicate that the doubling constant, $qv$, is in general a function of all three vibrational quantum numbers. By analogy with past theoretical work on $l$-doubling one is led to the semi-emperical equation \underlin{{q}{v}}=\Sigma{i}{Q}{i}(\underlin{v}{i}+1) for the functional relationship, where $vi$ are the vibrational quantum numbers, i = 1, 2, 3, and the $Q1$ are called Coriolis constants. It is shown that the data fit this equation within experimental error.