Electronic transitions of palladium dimer.

The laser induced fluorescence spectrum of palladium dimer (Pd2) in the visible region between 480 and 700 nm has been observed and analyzed. The gas-phase Pd2 molecule was produced by laser ablation of palladium metal rod. Eleven vibrational bands were observed and assigned to the [17.1]³Π_g-X³Σ_u⁺ transition system. The bond length (ro) and vibrational frequency (ΔG1/2) of the ground X³Σ_u⁺ state were determined to be 2.47(4) Å and 211.4(5) cm-1, respectively. A molecular orbital energy level diagram was used to understand the observed ground and excited electronic states. This is the first gas-phase experimental investigation of the electronic transitions of Pd2. [ABSTRACT FROM AUTHOR]