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The radical cyclization reaction in the aqueous environment by Yorimitsu et al. is revisited using the RISM-SCF-cSED method, a hybrid of quantum chemistry and statistical mechanics theory for molecular liquids. The difference between the barrier height of the forward reaction from the intermediate E -rot, the cyclization step, and that of the backward reaction is crucial to the reaction yield. Considering the effect of hydrogen bonding through the RISM theory, we found that the barrier height for the forward reaction is lower, especially in water. In other words, considering microscopic solvation effects clearly shows the difference between water and DMSO solvents, explaining the remarkable acceleration of the reaction in the aqueous environment. [Display omitted] • The solvent effect on the radical cyclization reaction is analyzed theoretically. • Water solvent promotes the cyclization reaction by lowering its transition state. • Hydrogen bond around C O oxygen atom plays a crucial role on solvent effect of water. • The change in solvation structure along with the C C bond formation is also revealed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Single-phase samples were prepared by the sol–gel combustion method. • The macroscopic magnetism at room temperature was judged by the magnetization curve and Mössbauer spectrum. • A good thermomagnetic curve was fitted by molecular field theory, and the exact exchange constant was obtained. • The special thermally induced spin behavior of A-site Pr3+ ions are described. Ultrafast spin control plays a pivotal role in condensed matter physics. In this study, we analyzed the macroscopic magnetization of the PrFe 0.1 Cr 0.9 O 3 system by molecular field model fitting. And the whole process of system spin reorientation is accurately calculated in the fitting process. It is found that, unlike the rare-earth perovskites we have previously studied, PrFe 0.1 Cr 0.9 O 3 exhibits spin-reversion properties during the reorientation process. This research will lay a theoretical foundation for precise spin control in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 3D Reference Interaction Site Model is used to explore liquid oleyl alcohol. • The 3D-RISM simulations produced the liquid oleyl alcohol structure qualitatively similar to the MD simulation. • The united atom TRAPPE force field is used for bulk susceptibility calculation of the liquid. • The molecular partitioning in alcohol/water media is calculated with RMSD of 0.48 unit. • A new QSAR model is presented for the partition function calculation. The 3D-RISM-KH molecular solvation theory is applied to liquid long chain unsaturated oleyl alcohol to explore the structure of the liquid and to calculate alcohol/water partition coefficients. The united atom TraPPE force field parameters resulted in comparable structural information between RISM and MD simulations. The RISM theory and the MD simulation point to a relatively ordered liquid structure of oleyl alcohol. The molecular partition coefficients were computed with a root mean square deviation of 0.48 unit via a predictive quantitative structure activity relationship. [ABSTRACT FROM AUTHOR]