THE BINDING-ENERGY OF NI+CENTER-DOT-CO2

The internally cold, gas-phase electrostatic complex of Ni+ with a sin gle carbon dioxide molecule, Ni+.OCO, is observed by resonant photodis sociation spectroscopy with visible light. Sharp bound-bound optical a bsorptions are detected via predissociation into Ni+ and CO2 fragments . A cutoff in the photofragmentation is observed below 17100 cm(-1) an d this represents the threshold for dissociation into the lowest quart et pathway. This places the binding energy of the Ni+.OCO complex at 1 .08 +/- 0.01 eV with respect to ground state Ni+ and CO2.