Isotopically resolved {ie30-01} electronic spectrum of Ag3 and calculation of its Jahn-Teller effects

Ag₃ was produced by pulsed-nozzle laser vaporisation and jet-cooled in a Ne supersonic expansion. Onecolor resonant two-photon ionisation (R2PI) spectra of the {ie30-02} transition of Ag₃ were separately measured for all four isotopic combinations. Long vibrational progressions are observed, involving clearly resolved bands at low energy, merging into a dense but resolvable spectrum up to 1000 cm¹ above the origin. Both the ground {ie30-03} and excited {ie30-04} states of Ag3 are susceptible to Jahn-Teller distortion along the degenerate e′ bending coordinate. The Jahn-Teller analysis includes both linear and quadratic terms, simultaneously with the spin-orbit coupling. Following extensive parameter fitting, the absorption spectrum is calculated, and bands assigned. The spin-orbit splitting is quenched below the localization energy, but becomes observable ≈ 300 cm^-1 above the origin.