Knowledge Bank

“The emission spectrum of $N215$ has been studied in the region 2000-9000 {\AA} with n view to studying the vibrational structure of some of the weaker systems. In the eases of the Herman infrared bands and the Gayden-Herman green bands it has been possible to between two alternative vibrational schemes which have been suggested. In the near-ultraviolet spectrum it is shown that the $d\rightarrow a, m \rightarrow a, r’ \rightarrow a, s’ \rightarrow $a. and $L\prime \to a$ progressions all arise from upper levels with $v>O$. The possibility that some of these progressions may belong to a single system will be discussed.”