HOLGER SCHNEIDER, KAITO TAKAHASHI, REX T. SKODJE, J. MATHIAS WEBER, JILA, NIST, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309.
Formic acid binds to the SF6- anion in a single (OH-F) H bond, with the CH group weakly tethered to a neighboring F atom. Similar to the case of SF6- H2O complexes, the SF bond involved in the (OH-F) H bond is significantly stretched and weakened by the attachment of the HCOOH ligand. The complex undergoes a reaction upon infrared absorption of one quantum in the OH or CH stretching mode of the formic acid moiety, leading predominantly to the formation of SF4-, HF, and CO2. The reaction can be inhibited by attachment of two Ar atoms. We present IR photodissociation spectroscopy results and theoretical data illustrating the reaction mechanism.