Reinvestigate the C²Π-X²Π(0, 0) Band of AgO

The C^2\Pi - X^2\Pi (0, 0) band of AgO has been reinvestigated by laser induced fluorescence spectroscopy with a spectral resolution of \sim 0.02 cm ^-1 . The AgO molecules are produced by discharging a gas mixture of O _2 /Ar with silver needle electrodes in a supersonic jet expansion. By employing a home-made narrowband single longitude mode optical parametric oscillator (SLM-OPO) as the laser source, high-resolution spectra of the C^2\Pi - X^2\Pi (0, 0) band have been recorded for both ^107 Ag ^16 O and ^109 Ag ^16 O isotopologues. The spectroscopic constants of the C^2\Pi state are consequently determined, with the ^109 Ag ^16 O one being reported for the first time. The nature of the spin-orbit coupling effect in the C^2\Pi state is proposed to be due to state mixing with the nearby repulsive ^4\Sigma^- and ^4\Pi states.