The evolutionarily perfected catalytic sites in most hydrogenase enzymes are comprised of two base metals, bridged by sulfurs and buried deeply in the proteins, that function in hydrogen production from protons and electrons, or, according to the reverse reaction, to use H₂ as a fuel source.  We strive to understand how such molecular constructions of nickel and iron, or two iron atoms, ligated by carbon monoxide and cyanide so as to be surprisingly familiar to organometallic chemists, are able to efficiently compete with platinum in fuel cell assemblies.  It is our hypothesis that the [FeFe]H₂ase enzyme has the diiron organometallic trapped in an “entatic” high energy state which is rotated relative to analogous compounds on the chemist’s benchtop. Such a rotated state is stabilized in non-symmetric compounds outfitted with electron-donating ligands.  Computational studies further suggest the need for steric hindrance at the bridgehead of the S to S linker.  Synthetic efforts are focused on such [Fe^IFe^I] compounds which are evaluated as electrocatalysts for H₂ production.  At the Fe^IIFe^I/II redox level, H₂ uptake and activation is assayed by isotopic exchange in D₂O/H₂ mixtures.  The ultimate goal is the synthesis of base metal, hydrogen-processing catalysts ultimately for replacement of platinum in fuel cell electrodes..