PROJECT SUMMARY This administrative supplement request is proposed to fund procurement of a miniature fiber-optic UV/visible/near-IR spectrometer with accompanying software and sampling accessories. This equipment will significantly accelerate research in the parent award, whose goals are to advance multimetallic catalysis by addressing open scientific questions and challenges regarding (a) biomimetic model complexes inspired by metalloenzymes, and (b) abiological catalysts for organic synthesis methodology. A majority of the research plan during the current grant cycle focused on topic (a), which is the one that will be aided by the proposed procurement of an Ocean-HDX-XR spectrometer with accompanying sampling tools from Ocean Insights. This instrument will complement existing core facilities at the research site, which offer a Windows-95 era UV/visible spectrometer with no near-IR capabilities. Not only will the Ocean-HDX-XR provide security against catastrophic failure of this aging instrument and expand the spectral window in the near-IR region, but it will also facilitate measurements under inert atmosphere by being transferable into gloveboxes using Wifi connectivity. The addition of a dip probe accessory will also facilitate in-situ reaction monitoring and characterization of reactive intermediates. Case studies are presented that highlight the potential benefits of these added capabilities to understand reaction pathways of the CuZ site of nitrous oxide reductase, the Mo/Cu active site of aerobic carbon monoxide dehydrogenase, and other metalloenzymes being studied under the parent award.