Characterization of an activated iridium water splitting catalyst using infrared photodissociation of H2 tagged ions.
We report the vibrational predissociation spectra of two related organometallic half-sandwich iridium species which have been recently reported as activated intermediates in the context of homogenous water oxidation. These compounds are extracted from solution into a cryogenic photofragmentation mass spectrometer and "tagged" with weakly bound H(2) molecules that do not significantly perturb the intrinsic structures of the ions. The resulting spectra display very sharp (∼5 cm(-1)), well-resolved bands that provide a stringent test for electronic structure calculations, and are accurately recovered by harmonic predictions for the bare species. The spectra reveal subtle distortions of the ligand structure when a solvent molecule (acetonitrile) is directly coordinated with the metal center.
Sterling Chemistry Laboratory, Yale University, P.O. Box 208107, New Haven, CT 06520, USA.
Etienne
E
Garand
Joseph A
JA
Fournier
Michael Z
MZ
Kamrath
Nathan D
ND
Schley
Robert H
RH
Crabtree
Mark A
MA
Johnson