ROTATIONAL STRUCTURE OF THE $A'_{5}\Delta - x'_{5}\Pi$ ELECTRONIC TRANSITION OF CrO

$^{1}$T. C. Devore and J. L. Gole, Chem. Phys. 133, 95 (1989). $^{2}$A. 8-C Cheung, W. Zyrnicki, and A. J. Merer, J. Mol. Spectroac. 104, 315 (1984).Author Institution: Department of Chemistry, University of British ColumbiaThe laser-induced fluorescence spectrum of CrO was recorded at Doppler-limited resolution in the near-infrared employing a single-frequency tunable cw Ti:sapphire ring laser. The (O,O) band centred near 8400 {\AA} consists of five unperturbed sub-bands each characterized by readily identifiable P, Q, and R branches. Rotational analysis confirmed the nature of the excited state of the red system of CrO as $^{5}\Delta$ in accord with a recent low-resolution $study^{1}$. Spectroscopic measurements from the present analysis were combined with those of the $A^{5}\Sigma^{+} - X^{5}\Pi$ (0,0) transition recorded previously using an FTIR $spectrometer^{2}$. A weighted nonlinear least-squares fit furnished improved molecular parameters for the $A^{5}\Sigma^{+}$ and $X^{5}\Pi$ electronic states as well as the first set of reliable constants for the $A^{5}\Delta$ state