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Aminopolycarboxylate chelates are emerging as a promising class of electrolyte materials for aqueous redox flow batteries, offering tunable redox potentials, solubility, and pH stability through careful selection of ligands and transition metal ions. Despite their potential, the impact of molecular structure modifications on the electronic and electrochemical properties of these chelates remains underexplored. Here, we examine how introducing a hydroxyl group, often employed for its solubilizing properties, to the backbone of CrPDTA, a reference chelate material, significantly changes the thermodynamics and kinetics of the chelate’s redox process. We correlate changes in molecular and electronic structures to different electrochemical responses resulting from the hydroxyl addition and show that the introduction of this functional group leads to a distortion in the octahedral coordination of chromium. Furthermore, increased anisotropic spin density and non‐integral oxidation state changes in the Cr metal center result in a larger barrier for electron transfer in CrPDTA‐OH. We demonstrate that preserving a hexacoordinate chelate structure across a broad pH range is crucial for efficient flow battery application and emphasize that ligand modifications aimed at enhancing solubility must avoid distorting the octahedral coordination of the transition metal. 

The directional deformation of liquid crystalline elastomers (LCEs) is predicated on alignment, enforced by various processing techniques. Specifically, surface-aligned LCEs can exhibit higher temperature thermomechanical responses and weakened strain−temperature coupling in comparison to LCEs subjected to mechanical or rheological alignment. Recently, we reported enhanced stimuli response of mechanically aligned LCEs containing supramolecular liquid crystals. Here, we prepare supramolecular LCEs via surface-enforced alignment to study the impact of the supramolecular bond strength and intermolecular forces. This was evaluated using oxybenzoic acid (OBA) derivatives with and without pendant methyl groups as well as via oxybenzoic acid-pyridine complexes. Increased incorporation of supramolecular mesogens reduces the isotropic transition temperature and generally increases the strain−temperature coupling. The number of elastically active strands per unit volume, hydrogen bond conformations, and network morphology are affected by the supramolecular mesogens and influence the observed stimuli response. Overall, reduced intermolecular interactions correlate with more desirable actuation properties, demonstrating the influence of the supramolecular mesogen’s structure. 

Magic-sized clusters (MSCs) are kinetically stable, atomically precise intermediates along the quantum dot (QD) reaction potential energy surface. Literature precedent establishes two classes of cadmium selenide MSCs with QD-like inorganic cores: one class is proposed to be cation-rich with a zincblende crystal structure, while the other is proposed to be stoichiometric with a “wurtzite-like” core. However, the wide range of synthetic protocols used to access MSCs has made direct comparisons of their structure and surface chemistry difficult. Furthermore, the physical and chemical relationships between MSC polymorphs are yet to be established. Here, we demonstrate that both cation-rich and stoichiometric CdSe MSCs can be synthesized from identical reagents and can be interconverted through the addition of either excess cadmium or selenium precursor. The structural and compositional differences between these two polymorphs are contrasted using a combination of 1H NMR spectroscopy, X-ray diffraction (XRD), pair distribution function (PDF) analysis, inductively coupled plasma optical emission spectroscopy, and UV–vis transient absorption spectroscopy. The subsequent polymorph interconversion reactions are monitored by UV–vis absorption spectroscopy, with evidence for an altered cluster atomic structure observed by powder XRD and PDF analysis. This work helps to simplify the complex picture of the CdSe nanocrystal landscape and provides a method to explore structure–property relationships in colloidal semiconductors through atomically precise synthesis.