Unusual cooperativity effects between halogen bond and donor-acceptor interactions: The role of orbital interaction

The energies of unoccupied and occupied orbitals were used as the correlation parameters between the electronic and adsorptive properties of organic molecules. A model describing the chemisorption of organic compounds on CaCO3 involving two types of interaction, i.e. two-electron, donor–acceptor interaction HOMO(adsorbent) → LUMO(adsorbate) and four-electron, three-orbital interaction HOMO(adsorbent) → {LUMO(adsorbate) + HOMO(adsorbate)}, was proposed. It was concluded that strengthening of the bond involved in chemisorption occurred if the energies of the occupied orbitals associated with the adsorbate and adsorbent were concurrent.

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Synergetic effects in multiphase catalysts: the role of FeSbO4 as donor—acceptor of spillover oxygen

Catalysis Today ◽

10.1016/s0920-5861(96)00184-8 ◽

1996 ◽

Vol 32 (1-4) ◽

pp. 311-319 ◽

Cited By ~ 14

Author(s):

S.R.G. Carrazán ◽

L. Cadus ◽

Ph. Dieu ◽

P. Ruiz ◽

B. Delmon

Keyword(s):

Synergetic Effects ◽

Donor Acceptor ◽

Multiphase Catalysts

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Computational study on the mechanism of metal-free photochemical borylation of aryl halides

10.22541/au.162550161.13972740/v1 ◽

2021 ◽

Author(s):

Chenhao Tu ◽

Nana Ma ◽

Qingli Xu ◽

Wenyue Guo ◽

Lanxin Zhou ◽

...

Keyword(s):

Density Functional ◽

Uv Light ◽

Computational Study ◽

Halogen Bond ◽

Bond Cleavage ◽

Aryl Halides ◽

Homolytic Cleavage ◽

Functional Theory ◽

Aryl Radicals

C-radical borylation is an significant approach for the construction of carbon−boron bond. Photochemical borylation of aryl halides successfully applied this strategy. However, precise mechanisms, such as the generation of aryl radicals and the role of base additive(TMDAM) and water, remain controversy in these reactions. In this study, photochemical borylation of aryl halides has been researched by density functional theory (DFT) calculations. Indeed, the homolytic cleavage of the C−X bond under irradiation with UV-light is a key step for generation of aryl radicals. Nevertheless, the generation of aryl radicals may also undergo the process of single electron transfer and the heterolytic carbon-halogen bond cleavage sequence, and the latter is favorable during the reaction.

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Two-electron transfer stabilized by excited-state aromatization

Nature Communications ◽

10.1038/s41467-019-12986-w ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Jinseok Kim ◽

Juwon Oh ◽

Seongchul Park ◽

Jose L. Zafra ◽

Justin R. DeFrancisco ◽

...

Keyword(s):

Electron Transfer ◽

Excited State ◽

Excited States ◽

Transfer Process ◽

Comprehensive Understanding ◽

Electron Transfer Process ◽

Photoactive Materials ◽

Donor Acceptor ◽

Scientific Significance

Abstract The scientific significance of excited-state aromaticity concerns with the elucidation of processes and properties in the excited states. Here, we focus on TMTQ, an oligomer composed of a central 1,6-methano[10]annulene and 5-dicyanomethyl-thiophene peripheries (acceptor-donor-acceptor system), and investigate a two-electron transfer process dominantly stabilized by an aromatization in the low-energy lying excited state. Our spectroscopic measurements quantitatively observe the shift of two π-electrons between donor and acceptors. It is revealed that this two-electron transfer process accompanies the excited-state aromatization, producing a Baird aromatic 8π core annulene in TMTQ. Biradical character on each terminal dicyanomethylene group of TMTQ allows a pseudo triplet-like configuration on the 8π core annulene with multiexcitonic nature, which stabilizes the energetically unfavorable two-charge separated state by the formation of Baird aromatic core annulene. This finding provides a comprehensive understanding of the role of excited-state aromaticity and insight to designing functional photoactive materials.

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Leading Interaction Components in the Structure and Reactivity of Noble Gases Compounds

Molecules ◽

10.3390/molecules25102367 ◽

2020 ◽

Vol 25 (10) ◽

pp. 2367

Author(s):

Francesca Nunzi ◽

Giacomo Pannacci ◽

Francesco Tarantelli ◽

Leonardo Belpassi ◽

David Cappelletti ◽

...

Keyword(s):

Chemical Bond ◽

Theoretical Approach ◽

Noble Gases ◽

Halogen Bond ◽

Noble Gas ◽

Anomalous Behavior ◽

Type Interaction ◽

Long Life ◽

Weak Chemical

The nature, strength, range and role of the bonds in adducts of noble gas atoms with both neutral and ionic partners have been investigated by exploiting a fine-tuned integrated phenomenological–theoretical approach. The identification of the leading interaction components in the noble gases adducts and their modeling allows the encompassing of the transitions from pure noncovalent to covalent bound aggregates and to rationalize the anomalous behavior (deviations from noncovalent type interaction) pointed out in peculiar cases. Selected adducts affected by a weak chemical bond, as those promoting the formation of the intermolecular halogen bond, are also properly rationalized. The behavior of noble gas atoms excited in their long-life metastable states, showing a strongly enhanced reactivity, has been also enclosed in the present investigation.

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Supramolecular Assemblies in Silver Complexes: Phase Transitions and the Role of the Halogen Bond

Inorganic Chemistry ◽

10.1021/acs.inorgchem.0c00256 ◽

2020 ◽

Vol 59 (6) ◽

pp. 4140-4149

Author(s):

Giulia Bonfant ◽

Matteo Melegari ◽

Davide Balestri ◽

Francesco Mezzadri ◽

Vittoria Marzaroli ◽

...

Keyword(s):

Phase Transitions ◽

Halogen Bond ◽

Supramolecular Assemblies ◽

Silver Complexes

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Halogen-Bond Assisted Photoinduced Electron Transfer

Molecules ◽

10.3390/molecules24234361 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4361

Author(s):

Bogdan Dereka ◽

Ina Fureraj ◽

Arnulf Rosspeintner ◽

Eric Vauthey

Keyword(s):

Electron Transfer ◽

Excited State ◽

Ground State ◽

Halogen Bond ◽

Quenching Rate ◽

Excited Complex ◽

Diffusion Controlled ◽

Donor Acceptor ◽

Quenching Rate Constant ◽

Excited State Population

The formation of a halogen-bond (XB) complex in the excited state was recently reported with a quadrupolar acceptor–donor–acceptor dye in two iodine-based liquids (J. Phys. Chem. Lett. 2017, 8, 3927–3932). The ultrafast decay of this excited complex to the ground state was ascribed to an electron transfer quenching by the XB donors. We examined the mechanism of this process by investigating the quenching dynamics of the dye in the S1 state using the same two iodo-compounds diluted in inert solvents. The results were compared with those obtained with a non-halogenated electron acceptor, fumaronitrile. Whereas quenching by fumaronitrile was found to be diffusion controlled, that by the two XB compounds is slower, despite a larger driving force for electron transfer. A Smoluchowski–Collins–Kimball analysis of the excited-state population decays reveals that both the intrinsic quenching rate constant and the quenching radius are significantly smaller with the XB compounds. These results point to much stronger orientational constraint for quenching with the XB compounds, indicating that electron transfer occurs upon formation of the halogen bond.

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