Knowledge Bank

The electronic absorption spectrum of chromyl chloride vapor reveals substantial vibrational and rotational structure based on electronic $origin1$ at 5800$\backslash AA$. Five progressions are observed, each with a progression interval of 136$cm-1$. Although a single vibronic level fluorescence study of the vapor at room $temperature2$ and a fluorescence excitation spectrum of $CrO2Cl2$ cooled in a free jet $expansion3$ have been published, the vibrational and rotational analyses of this system are incomplete. High resolution ($0.03cm-1$)room temperature absorption spectra of isotopically pure $CrO235Cl2$ have provided detailed rotational contours at high J of many members of each progression, permitting assignments of the vibronic symmetries of the bands. Isotopic splittings, determined from measurements of similar spectra of samples with a natural abundance of Cl isotopes, have also been obtained. From this information a more complete vibrational analysis of the system has been carried out.