Knowledge Bank

Pure rotational transitions have been observed in the metastable $a3\Pi$ State of carbon monoxide, generated in a glow discharge through a CO-He mixture at near-ambient temperature. Well-resolved spectra at 393.6 $\mu m(HCOOH)$ and 458.5 $\mu m(HCOOH)$ ore assigned to the $J=6\to 7$ and $J=5\to 6$ transitions in the $\Omega =2$ state, respectively. A more overlapped spectrum observed at 601.9 $\mu m(CH2CHCI)$ is tenatively attributed to the $J=4\to 5$ transition in $\Omega =1$. Another weak series of lines found at 699 $\mu m(CH3OH)$ appears to be the $N=7\to 8$ transition in the more short-lived $a\prime 3\Sigma +$ state of CO. These results are being analyzed along with earlier data In hopes of obtaining an uncorrelated, physically meaningful set of molecular parameters for the $a3\Pi$ state.