In an study, Tsuneda and Taketsugu (, 2018, , 24992-24999) discuss the Fenton reaction, the reaction of Fe with HO. They claim that reaction is endergonic and therefore introduce a new intermediate, a monovalent iron complex. I show here that kinetically and thermodynamically such a monovalent iron complex cannot be formed.
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Unveiling the Nature of Chemical Bonds in Real Space.
J Am Chem Soc
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Department of Applied Physics, Nagoya University, Nagoya 464-8603, Japan.
Recent advent of diverse chemical entities necessitates a re-evaluation of chemical bond concepts, underscoring the importance of experimental evidence. Our prior study introduced a general methodology, termed Core Differential Fourier Synthesis (CDFS), for mapping the distribution of valence electron density (VED) in crystalline substances within real space. In this study, we directly compare the VED distributions obtained through CDFS with those derived from high-accuracy theoretical calculation using long-range corrected density functional theory, which quantitatively reproduces accurate orbital energies.
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Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
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Sci Rep
January 2024
Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan.
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Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
The roles of singlet fission in the triplet generation of silicon phthalocyanine (SiPc), a compound analogous to the IRDye700DX photosensitizer used in near-infrared photoimmunotherapy, are investigated by considering the energetical relation between the excitations of this compound. These excitations are obtained through spin-flip long-range corrected time-dependent density functional theory calculations. To initiate singlet fission, chromophores must meet two conditions: (1) near-degenerate low-lying singlet and quintet (triplet-triplet) excitations with a considerable energy gap of the lowest singlet and triplet excited states and (2) moderate π-stacking energy of chromophores, which is higher than but not far from the solvation energy, to facilitate the dissociation and generation of triplet-state chromophores.
View Article and Find Full Text PDFTotal and orbital density-based analyses of molecules revealing long-range interaction regions.
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Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan.
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