Knowledge Bank

The emission spectrum of BN has been investigated in the 1800-$10,000cm-1$ region using a Fourier transform spectrometer. BN was formed in a microwave discharge of He with a trace of $BCI3$; and $N2$. The bands with Q-heads at 3339, 3514, 4827 and $5024cm-1$ have been assigned as the 1-1, 0-0, 2-1, and 1-0 bands of the $b1\Pi -a1\Sigma +$ transition, analogous to the $A1\Pi u-X1\Sigma g-$ (Phillips) system of the isoelectronic molecule $C2$ The rotational analysis of these bands has provided the molecular constants for the b^{\prime}II and $a1\Sigma +$ states. This work represents the first observation of the $b1\Pi -a1\Sigma +$ transition of BN in gas phase.