The Beta Bands of Nitric Oxide. I. Measurements and Quantum Analysis

Band structure and wave-number data for band lines. Using an active nitrogen source, the $\beta$ bands of NO included in the region of 2300 to 5300A have been photographed in the second order of a 21-ft. Rowland concave grating. Each complete band consists of two sub-bands with a $P$ and an $R$ branch of the ordinary type and also a very weak $Q$ branch. The latter is relatively more intense in the lower frequency sub-band. Here there are four missing lines in the otherwise continuous $P-R$ series, while there are two in the higher frequency sub-band. The lines of the latter are narrow doublets superficially resembling those of the violet CN bands. The six branches for each of eighteen bands have been measured, and wave-numbers are tabulated for 20 to 30 lines in the $P$ and $R$ branches, and for the few visible members of the $Q$ branches. The bands measured include nine of the strong $n^{\prime }=0\mathrm{}$ progression ($n^{\prime \prime }=4\mathrm{} \mathrm{to} 12$), three of $n^{\prime }=1(n^{\prime \prime }=6, 11, 13)$, four of $n^{\prime }=2(n^{\prime \prime }=9, 13, 14, 15)$, and two of $n^{\prime }=3(n^{\prime \prime }=8, 16)$.