PHOTOIONIZATION SPECTROSCOPY OF AU-AR

Resonant photoionization spectroscopy probes the new metal van der Waa ls complex An-Ar. Band systems observed near 270 nm and 245 nm correla te to the spin-orbit components (P-2(1/2)<--S-2 and P-2(3/2)<--S-2) of the Au (6p<--6s) atomic transition. Extrapolated vibronic progression s yield the excited state convergence energy, which is combined with t he atomic asymptote to yield the ground state bond energy, D''(0)=130/-15 cm(-1). Lower limits for the excited state binding energies are D '(0)((2) Pi(1/2))greater than or equal to 338 cm(-1) and D'(0)((2) Pi( 3/2))greater than or equal to 654 cm(-1). The ionization potential is less than or equal to 9.208 eV. Au-Ar is compared to the Cu-RG and Ag- RG complexes studied previously. (C) 1997 Elsevier Science B.V.