First-ionization potential of ruthenium, rhodium, and palladium by double-resonance ionization spectroscopy

Abstract
The first-ionization potentials of ruthenium (Ru I), rhodium (Rh I), and palladium (Pd I) were determined, with significantly improved accuracy, to be 59 366.4(3), 60 160.1(4), and 67 242(1) cm−1, respectively, by double-resonance ionization spectroscopy performed on atomic beams produced by laser vaporization. The new values complete a reassessment of the first-ionization potentials of the second-row transition-metal series.