Exploration of the Dioxouranium Complex LUO2: 3D Supramolecular Architecture, Hirshfeld Surface Analysis, and Electrochemical Properties

Abstract

Abstract—In continuation of previous published works on the synthesis and crystallographic characterization of dioxouranium complexes with symmetrical NNOO tetradentate Schiff bases, we report herein deep investigations of the supramolecular features, and electrochemical properties of the studied crystal. This includes 3D molecular Hirshfeld surface analysis and visualization of the resulting three-dimensional supramolecular network. The analysis identifies H⋅⋅⋅C/C⋅⋅⋅H contacts as the main contributors to crystal packing, accounting for 34.7%. The 3D supramolecular network of LUO2 is formed through the overlap of chains, resulting in a porous structure along the (Oa) direction. The pores are uniform, non-circular, and approximately 9 Å in size along the shorter diagonal. In addition, the electrochemical properties of the uranyl complex, studied via cyclic voltammetry, revealed a quasi-reversible U(VI)/U(V) redox process with a half-wave potential (E1/2) of –1126 mV vs. SCE in DMF. Measurements using a glassy carbon electrode indicated diffusion-controlled redox behavior. Thermal studies indicate that the complex is non-volatile and a high thermal stability.