Unusual Square Pyramidal Chalcogenide Mo5 Cluster with Bridging Pyrazolate-Ligands

Abstract

The family of chalcogenide molybdenum clusters is well presented in the literature by a series of compounds of nuclearity ranging from binuclear to multinuclear articulating octahedral fragments. Clusters actively studied in the last decades were shown to be promising as components of superconducting, magnetic, and catalytic systems. Here, we report the synthesis and detailed characterization of new and unusual representatives of chalcogenide clusters: square pyramidal complexes [{Mo5(μ3-Se)i4(μ4-Se)i(μ-pz)i4}(pzH)t5]1+/2+ (pzH = pyrazole, i = inner, t = terminal). Individually obtained oxidized (2+) and reduced (1+) forms have very close geometry (proven by single-crystal X-ray diffraction analysis) and are able to reversibly transform into each other, which was confirmed by cyclic voltammetry. Comprehensive characterization of the complexes, both in solid and in solution, confirms the different charge state of molybdenum in clusters (XPS), magnetic properties (EPR), and so on. DFT calculations complement the diverse study of new complexes, expanding the chemistry of molybdenum chalcogenide clusters.

Synergistic Performance Boosts of Dopamine‐Derived Carbon Shell Over Bi‐metallic Sulfide: A Promising Advancement for High‐Performance Lithium‐Ion Battery Anodes

“…[ 30 ] After undergoing sulfurization and carbonization processes, trace amounts of Mo 6+ were observed in the Mo 3d 5/2 and 3d 3/2 peaks, likely attributed to the hydrothermal sulfurization conditions. [ 31 ] Along with the Mo 3d peaks, a low‐intensity S 2s peak, originating from the solitary sulfur deposits, can be observed on the spectra of CoMoS and CoMoS@NC. Figure 4c shows the comparative S 2p core level spectra of the CoMoS and CoMoS@NC samples.…”