Various models for the iron hydrogenase active site covalently linked to a ruthenium pho...

Various models for the iron hydrogenase active site covalently linked to a ruthenium photosensitizer have been synthesized as candidates for light-driven proton reduction. A prototype for this class of complexes features a phenylacetylene linker between the iron and ruthenium portions of the molecule (S. Ott, M. Borgström, M. Kritikos, R. Lomoth, J. Bergquist, B. Åkermark, L. Hammarström, L. Sun, Inorg. Chem. , 2004 , 43 , 4683). Sketch the target complex. Provide three reasons for inclusion of the phenylacetylene linker, and assign the two most intense bands in its electronic absorption spectrum (solid line in spectrum). Briefly explain why this complex is unable to induce proton reduction.