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The analytical chemistry of phosphorus-containing materials is often impeded by the long measurement times and relatively large sample masses needed for 31 P NMR spectroscopy, by the scarcity and access limitations of synchrotron beamlines operating in the energy range of the P K-edge, by the challenges posed by species interconversion during liquid extraction, and by the considerable air-sensitivity typical of many phosphorus-containing materials and nanophases. To this end, we report the design and operation of a new laboratory-based spectrometer to simultaneously perform P Kα and Kβ X-ray emission spectroscopy (XES) while being housed in a research-grade controlled-atmosphere glovebox. Demonstration studies on nickel phosphide nanophases illustrate the importance of air-free XES and the value of simultaneous Kα and Kβ spectroscopy for identifying the P oxidation state and for investigating nanoscale influences on valence level electronic structures. 

Redox-active multimetallic platforms with synthetically addressable and hemilabile active sites are attractive synthetic targets for mimicking the reactivity of enzymatic co-factors toward multielectron transformations. To this end, a family of ternary clusters featuring three edge metal sites anchored on a [Co 6 Se 8 ] multimetallic support via amidophosphine ligands are a promising platform. In this report, we explore how small changes in the stereoelectronic properties of these ligands alter [Co 6 Se 8 ] metalloligand formation, but also substrate binding affinity and strength of the edge/support interaction in two new ternary clusters, M 3 Co 6 Se 8 L 6 (M = Zn, Fe; L (−) = Ph 2 PN (−)i Pr). These clusters are characterized extensively using a range of methods, including single crystal X-ray diffraction, electronic absorption spectroscopy and cyclic voltammetry. Substrate binding studies reveal that Fe 3 Co 6 Se 8 L 6 resists coordination of larger ligands like pyridine or tetrahydrofuran, but binds the smaller ligand CN t Bu. Additionally, investigations into the synthesis of new [Co 6 Se 8 ] metalloligands using two aminophosphines, Ph 2 PN(H) i Pr (L H ) and i Pr 2 PN(H) i Pr, led to the synthesis and characterization of Co 6 Se 8 L H 6 , as well as the smaller clusters Co 4 Se 2 (CO) 6 L H 4 , Co 3 Se(μ 2 -PPh 2 )(CO) 4 L H 3 , and [Co(CO) 3 ( i Pr 2 PN(H) i Pr)] 2 . Cumulatively, this study expands our understanding on the effect of the stereoelectronic properties of aminophosphine ligands in the synthesis of cobalt chalcogenide clusters, and, importantly on modulating the push–pull dynamic between the [Co 6 Se 8 ] support, the edge metals and incoming coordinating ligands in ternary M 3 Co 6 Se 8 L 6 clusters.