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This Zip file contains the cartesian coordinates of optimized stationary points of the O(3P, 1D) + HCCCN(X1Σ+) potential energy surface published in our article “Reactions O(3P, 1D) + HCCCN(X1Σ+) (Cyanoacetylene): Crossed-Beam and Theoretical Studies and Implications for the Chemistry of Extraterrestrial Environments” (J. Phys. Chem. A 2023, 127, 3, 685–703), that can be found in https://doi.org/10.1021/acs.jpca.2c07708. All calculations have been performed with Gaussian 09, Revision D.01. All structures have been optimized at B3LYP/aug-cc-pVTZ level of theory.

An analytic potential function consistent with the Marcus equation for activation energy is formulated and used to reveal new insights into the activation process in chemical reactions. As for the Marcus equation, the new potential function depends only on two parameters, the reaction energy and the activation energy (or the so-called Marcus intrinsic activation energy). Combination of the Marcus potential with the reaction force analysis provides two-parameter analytic expressions for the reaction force, reaction force constant, and reaction works. Moreover, since the parameters necessary to define the Marcus potential energy function can be obtained experimentally, the present model may produce experimental analytic potentials allowing for new and interesting applications, thus emerging as a powerful tool to characterize activation processes in chemical reactions.

Abstract District heating will have an increasing role in the decarbonization of energy systems and in improving the security of supply. Although the electrification of district heating via heat pumps and heat storage is seen as the main path to decarbonization, green hydrogen could also be an important energy source for covering peak demand, providing long-term storage in power-to-gas solutions and backup. The study’s research question was to identify the potential pathways for replacing natural gas in district heating with hydrogen. Should we focus on using hydrogen and build appropriate infrastructure, or should we use hydrogen-derived synthetic gas, for which we already have an infrastructure? A review of publications was the method used in the study. The results show the existing technological solutions and associated costs for using either hydrogen or hydrogen-derived synthetic gas, i.e., methane.

Direct oxidation of pure Zn particles with CO2 is inhibited by an impervious ZnO scale. The presence of a ZnO diluent surface provides a site for an additional heterogeneous reaction of sublimated Zn that allows for a fast and high conversion of Zn. This is relevant to the efficient production of CO by the oxidation of Zn particles produced by the solar thermal dissociation of ZnO that are generally contaminated by the recombined ZnO. The overall reaction mechanism thus involves the sublimation of Zn(g) from the Zn surface, its transport to the ZnO diluent surface, and its subsequent heterogeneous reaction with CO2 on this surface. To elucidate the most relevant of those elementary steps different kinetic models were tested against a broad set of isothermal thermogravimetric data acquired at different temperatures, CO2-concentrations, and initial ZnO contents. The overall rate was found to be controlled by the transport of Zn(g) to the ZnO diluent surface and the reaction of the chemisorbed CO2 either with Zn(g) or with Zn incorporated from gas phase into the ZnO lattice surface sites. Increasing the initial content of ZnO diluent increases the effectiveness of the heterogeneous reaction at the ZnO diluent surface which facilitates the sublimation of Zn and appears to render the ZnO product scale surrounding unreacted Zn more permeable. Chemical Engineering Science, 165 ISSN:0009-2509

Solar-driven methane dry reforming via a ceria-based thermochemical redox cycle in a concentrating solar tower to produce solar syngas with a solar-to-fuel energy efficiency of 27%.

Saturated bicycles are becoming ever more important in the design and development of new pharmaceuticals. Here a new strategy for the synthesis of bicyclo[2.1.1]hexanes is described. These bicycles are significant because they have defined exit vectors, yet many substitution patterns are underexplored as building blocks. The process involves sensitization of a bicyclo[1.1.0]butane followed by cycloaddition with an alkene. The scope and mechanistic details of the method are discussed.

AbstractMolecular solar thermal (MOST) energy storage systems are getting increased attention related to renewable energy storage applications. Particularly, 2,3‐difunctionalized norbornadiene‐quadricyclane (NBD‐QC) switches bearing a nitrile (CN) group as one of the two substituents are investigated as promising MOST candidates thanks to their high energy storage densities and their red‐shifted absorbance. Moreover, such NBD systems can be prepared in large quantities (a requirement for MOST‐device applications) in flow through Diels‐Alder reaction between cyclopentadiene and appropriately functionalized propynenitriles. However, these acetylene precursors are traditionally prepared in batch from their corresponding acetophenones using reactive chemicals potentially leading to health and physical hazards, especially when working on a several‐grams scale. Here, we develop a multistep flow‐chemistry route to enhance the production of these crucial precursors. Furthermore, we assess the atom economy (AE) and the E‐factor showing improved green metrics compared to classical batch methods. Our results pave the way for a complete flow synthesis of NBDs with a positive impact on green chemistry aspects.