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Abstract Converting CO₂into industrially useful products is an appealing strategy for utilization of an abundant chemical resource. Electrochemical CO₂reduction (eCO₂R) offers a pathway to convert CO₂into CO and ethylene, using renewable electricity. These products can be efficiently copolymerized by organometallic catalysts to generate polyketones. However, the conditions for these reactions are very different, presenting the challenge of coupling microenvironments typically encountered for the transformation of CO₂into highly complex but desirable multicarbon products. Herein, we present a system to produce polyketone plastics entirely derived from CO₂and water, where both the CO and C₂H₄intermediates are produced by eCO₂R. In this system, a combination of Cu and Ag gas diffusion electrodes is used to generate a gas mixture with nearly equal concentrations of CO and C₂H₄, and a recirculatory CO₂reduction loop is used to reach concentrations of above 11% each, leading to a current‐to‐polymer efficiency of up to 51% and CO₂utilization of 14%. 

Abstract Electrochemically controlled redox-switchable polymerization uses an electric potential to bias the monomer selectivity of a catalyst. Many ferrocene-appended catalysts can exist in two oxidation states, a neutral reduced state and an oxidized cationic state. Electrochemical generation of the oxidized cationic state produces a charged species whose counteranion is determined by the identity of the supporting electrolyte anion. Herein, the role the counteranion has on monomer selectivity and polymerization kinetics is investigated. Minimal differences in monomer selectivity in the reduced state was found, however, in the oxidized state, the coordinating ability of the counteranion greatly influenced the rate of polymerization. How activity differences governed by the choice of electrolyte can be utilized to access desired diblock copolymers is also described. 

Achieving ultranarrow absorption linewidths in the condensed phase enables optical state preparation of specific non-thermal states, a prerequisite for quantum-enabled technologies. 

A nickel bromide complex supported by a non-innocent ferrocene-chelating heteroscorpionate ligand, [(fc(PPh₂)(BH(3,5-Me₂pz)₂)NiBr)] ((fc^P,B)NiBr, fc = 1,1′-ferrocenediyl, pz = pyrazole), was synthesized and characterized. 

The energetic disorder induced by fluctuating liquid environments acts in opposition to the precise control required for coherence-based sensing. Overcoming fluctuations requires a protected quantum subspace that only weakly interacts with the local environment. We report a ytterbium complex that exhibited an ultranarrow absorption linewidth in solution at room temperature with a full width at half maximum of 0.625 milli–electron volts. Using spectral hole burning, we measured an even narrower linewidth of 410 pico–electron volts at 77 kelvin. Narrow linewidths allowed low-field magnetic circular dichroism at room temperature, used to sense Earth-scale magnetic fields. These results demonstrated that ligand protection in lanthanide complexes could substantially diminish electronic state fluctuations. We have termed this system an “atomlike molecular sensor” (ALMS) and proposed approaches to improve its performance.