Knowledge Bank

Changes in the intensity distribution of fluorescence from individual rotational levels of the $A1II(v\prime =0.2)$ excited state of carbon monosulfide have been observed by using Stark and Zeeman effects to split zero field degeneracies of the excited levels. Coinciding atomic lines were used to excite molecular levels and fluorescence was detected at $90\circ$. The magnetic field at which the intensity change is half its maximum determines the $A1II$ radiative lifetime, $\tau$, if the molecular g-factor is assumed known. Similarly the electric field effect determines the ratio of $\mu 2$ to $\delta$ where $\mu$ and $\delta$ are respectively the dipole moment and lambda doubling of the excited rotational level. Lambda doublings have been estimated from optical data and an approximate dipole moment obtained. Values at present are: $\tau =2.38\pm 0.12\times 10-7sec.(v\prime =0.2),\mu =0.36\pm 0.12debye(v\prime =0)$.