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Morales A, Gonçalves C, Sournia-Saquet A, Vendier L, Lledós A, Baslé O, Bontemps S. Single electron reduction of NHC-CO 2-borane compounds. Chem Sci 2024; 15:3165-3173. [PMID: 38425525 PMCID: PMC10901481 DOI: 10.1039/d3sc06325a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 01/18/2024] [Indexed: 03/02/2024] Open
Abstract
The carbon dioxide radical anion [CO2˙-] is a highly reactive species of fundamental and synthetic interest. However, the direct one-electron reduction of CO2 to generate [CO2˙-] occurs at very negative reduction potentials, which is often a limiting factor for applications. Here, we show that NHC-CO2-BR3 species - generated from the Frustrated Lewis Pair (FLP)-type activation of CO2 by N-heterocyclic carbenes (NHCs) and boranes (BR3) - undergo single electron reduction at a less negative potential than free CO2. A net gain of more than one volt was notably measured with a CAAC-CO2-B(C6F5)3 adduct, which was chemically reduced to afford [CAAC-CO2-B(C6F5)3˙-]. This room temperature stable radical anion was characterized by EPR spectroscopy and by single-crystal X-ray diffraction analysis. Of particular interest, DFT calculations showed that, thanks to the electron withdrawing properties of the Lewis acid, significant unpaired spin density is localised on the carbon atom of the CO2 moiety. Finally, these species were shown to exhibit analogous reactivity to the carbon dioxide radical anion [CO2˙-] toward DMPO. This work demonstrates the advantage provided by FLP systems in the generation and stabilization of [CO2˙-]-like species.
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Affiliation(s)
- Agustín Morales
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne 31077 Toulouse Cedex 04 France
- Departament de Química, Universitat Autonoma de Barcelona 08193 Cerdanyola del Valles Catalonia Spain
| | - Caroline Gonçalves
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne 31077 Toulouse Cedex 04 France
| | - Alix Sournia-Saquet
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne 31077 Toulouse Cedex 04 France
| | - Laure Vendier
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne 31077 Toulouse Cedex 04 France
| | - Agustí Lledós
- Departament de Química, Universitat Autonoma de Barcelona 08193 Cerdanyola del Valles Catalonia Spain
| | - Olivier Baslé
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne 31077 Toulouse Cedex 04 France
| | - Sébastien Bontemps
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne 31077 Toulouse Cedex 04 France
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2
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Thøgersen J, Weidner T, Jensen F. The primary photolysis of aqueous carbonate di-anions. Phys Chem Chem Phys 2023; 25:14104-14116. [PMID: 37161877 DOI: 10.1039/d3cp00236e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We study the primary photolysis dynamics of aqueous carbonate, CO32-(aq), and hydrogen carbonate, HCO3-(aq), when they are excited at λ = 200 nm. The photolysis is recorded with sub-picosecond time resolution using UV pump-Vis probe and UV pump-IR probe transient absorption spectroscopy and interpreted with the aid of density functional theory calculations. When CO32- is excited via single photon absorption at λ = 200 nm, Φ(t = 20 ps) = 82 ± 5% of the excited di-anions either detach an electron or dissociate. The electron detachment takes place from the excited state in t < 1 ps and forms ground state CO3˙- and eaq-. Dissociation occurs from both the electronic ground and excited states of CO32-. Dissociation from the CO32- excited state is assisted by water molecules and forms CO2˙-, OH˙ and OH-. The dissociation occurs both directly from the Franck-Condon region in t < 1 ps and indirectly with a time constant of τ = 13.9 ± 0.5 ps as the excited state relaxes. Dissociation of vibrationally excited CO32- molecules in the electronic ground state is also assisted by water molecules and forms CO2 and two OH- anions. The dissociation and subsequent vibrational relaxation of CO2 occur with a time constant of τ = 10.2 ± 0.5 ps. The residual 1 - Φ(t = 20 ps) = 18 ± 5% of the excited CO32- di-anions return by internal conversion to the equilibrated CO32- ground state with a time constant of τ = 4.0 ± 0.4 ps. The extinction coefficient of aqueous hydrogen carbonate HCO3-(aq) at λ = 200 nm is an order of magnitude smaller than that of carbonate, so even though the hydrogen carbonate anions dominate the carbonate di-anions in the hydrogen carbonate solution, the primary photolysis of hydrogen carbonate is obscured by the photo-products of carbonate. Hence, we are unable to assess the primary photolysis of hydrogen carbonate. However, the weak one-photon absorption facilitates two-photon ionization of water, which forms hydronium, H3O+, cations. The sudden increase in the acidity induced by two-photon ionization protonates the ground state hydrogen carbonate molecules, thus offering a rare spectroscopic glimpse of aqueous carbonic acid.
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Affiliation(s)
- Jan Thøgersen
- Department of Chemistry, Aarhus University. Langelandsgade 140, DK-8000 Aarhus C, Denmark.
| | - Tobias Weidner
- Department of Chemistry, Aarhus University. Langelandsgade 140, DK-8000 Aarhus C, Denmark.
| | - Frank Jensen
- Department of Chemistry, Aarhus University. Langelandsgade 140, DK-8000 Aarhus C, Denmark.
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van der Linde C, Ončák M, Cunningham EM, Tang WK, Siu CK, Beyer MK. Surface or Internal Hydration - Does It Really Matter? JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:337-354. [PMID: 36744598 PMCID: PMC9983018 DOI: 10.1021/jasms.2c00290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/26/2023] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
The precise location of an ion or electron, whether it is internally solvated or residing on the surface of a water cluster, remains an intriguing question. Subtle differences in the hydrogen bonding network may lead to a preference for one or the other. Here we discuss spectroscopic probes of the structure of gas-phase hydrated ions in combination with quantum chemistry, as well as H/D exchange as a means of structure elucidation. With the help of nanocalorimetry, we look for thermochemical signatures of surface vs internal solvation. Examples of strongly size-dependent reactivity are reviewed which illustrate the influence of surface vs internal solvation on unimolecular rearrangements of the cluster, as well as on the rate and product distribution of ion-molecule reactions.
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Affiliation(s)
- Christian van der Linde
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020Innsbruck, Austria
| | - Milan Ončák
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020Innsbruck, Austria
| | - Ethan M. Cunningham
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020Innsbruck, Austria
| | - Wai Kit Tang
- Institute
of Research Management and Services (IPPP), Research and Innovation
Management Complex, University of Malaya, Kuala Lumpur50603, Malaysia
| | - Chi-Kit Siu
- Department
of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, PR China
| | - Martin K. Beyer
- Institut
für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020Innsbruck, Austria
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4
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Integrating Au@TiOx and Co sites in a tandem photocatalyst for efficient C-C coupling synthesis of ethane. J CO2 UTIL 2023. [DOI: 10.1016/j.jcou.2022.102333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Jin S, Heller J, van der Linde C, Ončák M, Beyer MK. Toward Detection of FeH + in the Interstellar Medium: Infrared Multiple Photon Dissociation Spectroscopy of Ar 2FeH . J Phys Chem Lett 2022; 13:5867-5872. [PMID: 35728268 PMCID: PMC9251756 DOI: 10.1021/acs.jpclett.2c01511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 06/15/2022] [Indexed: 06/10/2023]
Abstract
The iron hydride molecular cation FeH+ is expected to be present in the interstellar medium. Because of the lack of laboratory data, it is yet to be identified in spectrally resolved astronomic observations. As a benchmark for computational predictions and to guide an experimental search for the ro-vibrational lines of FeH+, we performed infrared multiple photon dissociation (IRMPD) spectroscopy of FeH+ tagged with two argon atoms. The Fe-H stretching mode in Ar2FeH+ is observed at 1860 cm-1. Combination bands of the Fe-H stretch with the two Fe-H bending and the asymmetric Fe-Ar stretching modes are observed at 2012 cm-1, 2054 cm-1, and 2078 cm-1. Quantum chemical calculations show that the molecule has C2v symmetry. The Ar-Fe-Ar bending mode at 46 cm-1 is significantly populated at the temperature of the experiment, causing thermal broadening of the Fe-H stretch and its redshift with increasing internal energy.
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ThOgersen J, Weidner T, Jensen F. The primary photo-dissociation dynamics of lactic acid: decarboxylation as CO2, CO2•-. Phys Chem Chem Phys 2022; 24:6880-6889. [DOI: 10.1039/d1cp05563a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study the primary photolysis dynamics of lactic acid induced by excitation at λ = 200 nm with the aim of elucidating how simple aqueous carboxyl acids react to the...
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Santana CS, Shine LS, Vieira LH, Passini RJ, Urquieta-González EA, Assaf EM, Gomes JF, Assaf JM. Effect of the Synthesis Method on Physicochemical Properties and Performance of Cu/ZnO/Nb 2O 5 Catalysts for CO 2 Hydrogenation to Methanol. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c02803] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Cássia S. Santana
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
| | - Luiza S. Shine
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
| | - Luiz H. Vieira
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
| | - Ricardo J. Passini
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
- Research Center on Advanced Materials and Energy, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
| | - Ernesto A. Urquieta-González
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
- Research Center on Advanced Materials and Energy, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
| | - Elisabete M. Assaf
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, São Paulo 13566-590, Brazil
| | - Janaina F. Gomes
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
| | - José M. Assaf
- Department of Chemical Engineering, São Carlos Federal University, São Carlos, São Paulo 13565-905, Brazil
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Clavaguéra C, Thaunay F, Ohanessian G. Manifolds of low energy structures for a magic number of hydrated sulfate: SO 42-(H 2O) 24. Phys Chem Chem Phys 2021; 23:24428-24438. [PMID: 34693943 DOI: 10.1039/d1cp03123f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Low energy structures of SO42-(H2O)24 have been obtained using a combination of classical molecular dynamics simulations and refinement of structures and energies by quantum chemical calculations. Extensive exploration of the potential energy surface led to a number of low-energy structures, confirmed by accurate calibration calculations. An overall analysis of this large set was made after devising appropriate structural descriptors such as the numbers of cycles and their combinations. Low energy structures bear common motifs, the most prominent being fused cycles involving alternatively four and six water molecules. The latter adopt specific conformations which ensure the appropriate surface curvature to form a closed cage without dangling O-H bonds and at the same time provide 12-coordination of the sulfate ion. A prominent feature to take into account is isomerism via inversion of hydrogen bond orientations along cycles. This generates large families of ca. 100 isomers for this cluster size, spanning energy windows of 10-30 kJ mol-1. This relatively ignored isomerism must be taken into account to identify reliably the lowest energy minima. The overall picture is that the magic number cluster SO42-(H2O)24 does not correspond to formation of a single, remarkable structure, but rather to a manifold of structural families with similar stabilities. Extensive calculations on isomerization mechanisms within a family indicate that large barriers are associated to direct inversion of hydrogen bond networks. Possible implications of these results for magic number clusters of other anions are discussed.
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Affiliation(s)
- Carine Clavaguéra
- Institut de Chimie Physique, Université Paris-Saclay - CNRS, UMR 8000, 91405 Orsay, France.
| | - Florian Thaunay
- Laboratoire de Chimie Moléculaire (LCM), CNRS, École Polytechnique, Institut Polytechnique de Paris, 91120 Palaiseau, France.
| | - Gilles Ohanessian
- Laboratoire de Chimie Moléculaire (LCM), CNRS, École Polytechnique, Institut Polytechnique de Paris, 91120 Palaiseau, France.
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Liu Y, Yang AA, Wang Y, Li WZ, Zhang XS, Luan J, Liu HZ, Wang ZG. Synthesis of two polymorphic Cu-based coordination polymers of 1,2,4-benzenetricarboxylic acid along with a carbon-coated composite for the selective degradation of organic dyes. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2021.122506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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10
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Justin A, Espín J, Kochetygov I, Asgari M, Trukhina O, Queen WL. A Two Step Postsynthetic Modification Strategy: Appending Short Chain Polyamines to Zn-NH 2-BDC MOF for Enhanced CO 2 Adsorption. Inorg Chem 2021; 60:11720-11729. [PMID: 34264652 DOI: 10.1021/acs.inorgchem.1c01216] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Functionalizing metal-organic frameworks (MOFs) with amines is a commonly used strategy to enhance their performance in CO2 capture applications. As such, in this work, a two-step strategy to covalently functionalize NH2-containing MOFs with short chain polyamines was developed. In the first step, the parent MOF, Zn4O(NH2-BDC)3, was exposed to bromoacetyl bromide (BrAcBr), which readily reacts with pendant -NH2 groups on the 2-amino-1,4-benzenedicarboxylate (NH2-BDC2-) ligand. 1H NMR of the digested MOF sample revealed that as much as 90% of the MOF ligands could be functionalized in the first step. Next, the MOF samples 60% of the ligands functionalized with acetyl bromide, Zn4O(NH2-BDC)1.2(BrAcNH-BDC)1.8, was exposed to several short chain amines including ethylenediamine (ED), diethylenetriamine (DETA), and tris(2-aminoethyl)amine (TAEA). Subsequent digested 1H NMR analysis indicated that a total of 30%, 28%, and 19% of the MOF ligands were successfully grafted to ED, DETA, and TAEA, respectively. Next, the CO2 adsorption properties of the amine grafted MOFs were studied. The best performing material, TAEA-appended-Zn4O(NH2-BDC)1.2(BrAcNH-BDC)1.8, exhibits a zero-coverage isosteric heat of CO2 adsorption of -62.5 kJ/mol, a value that is considerably higher than the one observed for the parent framework, -21 kJ/mol. Although the boosted CO2 affinity only leads to a slight increase in the CO2 adsorption capacity in the low-pressure regime (0.15 bar), which is of interest in postcombustion carbon dioxide capture, the CO2/N2 (15/85) selectivity at 313 K is 143, a value that is ∼35 times higher than the one observed for Zn4O(NH2-BDC)3, 4.1. Such enhancements are attributed to accessible primary amines, which were grafted to the MOF ligand. This hypothesis was further supported via in situ DRIFTS measurements of TAEA-Ac-Zn4O(NH2-BDC)1.2(BrAcNH-BDC)1.8 after exposure to CO2, which revealed the chemisorption of CO2 via the formation of hydrogen bonded carbamates/carbamic acid and CO2δ- species; the latter are adducts formed between CO2 and [amineH]+Br- salts that are produced during the amine grafting step.
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Affiliation(s)
- Anita Justin
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1951 Sion, Switzerland
| | - Jordi Espín
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1951 Sion, Switzerland
| | - Ilia Kochetygov
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1951 Sion, Switzerland
| | - Mehrdad Asgari
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1951 Sion, Switzerland
| | - Olga Trukhina
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1951 Sion, Switzerland
| | - Wendy L Queen
- Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1951 Sion, Switzerland
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11
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Asymmetric Solvation of the Zinc Dimer Cation Revealed by Infrared Multiple Photon Dissociation Spectroscopy of Zn 2+(H 2O) n ( n = 1-20). Int J Mol Sci 2021; 22:ijms22116026. [PMID: 34199627 PMCID: PMC8199724 DOI: 10.3390/ijms22116026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/20/2021] [Accepted: 05/26/2021] [Indexed: 11/17/2022] Open
Abstract
Investigating metal-ion solvation—in particular, the fundamental binding interactions—enhances the understanding of many processes, including hydrogen production via catalysis at metal centers and metal corrosion. Infrared spectra of the hydrated zinc dimer (Zn2+(H2O)n; n = 1–20) were measured in the O–H stretching region, using infrared multiple photon dissociation (IRMPD) spectroscopy. These spectra were then compared with those calculated by using density functional theory. For all cluster sizes, calculated structures adopting asymmetric solvation to one Zn atom in the dimer were found to lie lower in energy than structures adopting symmetric solvation to both Zn atoms. Combining experiment and theory, the spectra show that water molecules preferentially bind to one Zn atom, adopting water binding motifs similar to the Zn+(H2O)n complexes studied previously. A lower coordination number of 2 was observed for Zn2+(H2O)3, evident from the highly red-shifted band in the hydrogen bonding region. Photodissociation leading to loss of a neutral Zn atom was observed only for n = 3, attributed to a particularly low calculated Zn binding energy for this cluster size.
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12
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Pascher TF, Ončák M, van der Linde C, Beyer MK. Spectroscopy and photochemistry of copper nitrate clusters. Phys Chem Chem Phys 2021; 23:9911-9920. [PMID: 33908510 DOI: 10.1039/d1cp00629k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The investigation of copper nitrate cluster anions Cu(ii)n(NO3)2n+1-, n ≤ 4, in the gas phase using ultraviolet/visible/near-infrared (UV/vis/NIR) spectroscopy provides detailed insight into the electronic structure of the copper salt and its intriguing photochemistry. In the experimentally studied region up to 5.5 eV, the spectra of copper(ii) nitrate exhibit a 3d-3d band in the vis/NIR and well-separated bands in the UV. The latter bands originate from Ligand-to-Metal Charge Transfer (LMCT) as well as n-π* transitions in the nitrate ligands. The clusters predominantly decompose by loss of neutral copper nitrate in the electronic ground state after internal conversion or via the photochemical loss of a neutral NO3 ligand after a LMCT. These two decomposition channels are in direct competition on the ground state potential energy surface for the smallest copper nitrate cluster, Cu(ii)(NO3)3-. Here, copper nitrate evaporation is thermochemically less favorable. Population of π* orbitals in the nitrate ligands may lead to N-O bond photolysis. This is observed in the UV region with a small quantum efficiency, with photochemical loss of either nitrogen dioxide or an oxygen atom.
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Affiliation(s)
- Tobias F Pascher
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
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13
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Thøgersen J, Vaida V, Bregnhøj M, Weidner T, Jensen F. The primary photo-dissociation dynamics of lactate in aqueous solution: decarboxylation prevents dehydroxylation. Phys Chem Chem Phys 2021; 23:4555-4568. [PMID: 33605952 DOI: 10.1039/d0cp05650b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study the primary photolysis dynamics of aqueous lactate induced by photo-excitation at λ = 200 nm. Our calculations indicate that both decarboxylation and dehydroxylation are energetically possible, but decarboxylation is favoured dynamically. UV pump - IR probe transient absorption spectroscopy shows that the photolysis is dominated by decarboxylation, whereas dehydroxylation is not observed. Analysis of the transient IR spectrum suggests that photo-dissociation of lactate primarily produces CO2 and CH3CHOH- through the lowest singlet excited state of lactate, which has a lifetime of τ = 11 ps. UV pump - VIS probe transient absorption spectroscopy of electrons from the dissociating lactate anion indicates that the anionic electron from the CO2˙- fragment is transferred to the CH3CHOH˙ counter radical during the decarboxylation process, and CO2˙- is consequently only observed as a minor photo-product. The photo-dissociation quantum yield after the full decay of the excited state is Φ(100ps) = 38 ± 5%.
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Affiliation(s)
- Jan Thøgersen
- Dept. of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark.
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14
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Cunningham EM, Taxer T, Heller J, Ončák M, van der Linde C, Beyer MK. Microsolvation of Zn cations: infrared multiple photon dissociation spectroscopy of Zn +(H 2O) n (n = 2-35). Phys Chem Chem Phys 2021; 23:3627-3636. [PMID: 33524092 DOI: 10.1039/d0cp06112c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structures, along with solvation evolution, of size-selected Zn+(H2O)n (n = 2-35) complexes have been determined by combining infrared multiple photon photodissociation (IRMPD) spectroscopy and density functional theory. The infrared spectra were recorded in the O-H stretching region, revealing varying shifts in band position due to different water binding motifs. Concordant with previous studies, a coordination number of 3 is observed, determined by the sudden appearance of a broad, red-shifted band in the hydrogen bonding region for clusters n > 3. The coordination number of 3 seems to be retained even for the larger clusters, due to incoming ligands experiencing significant repulsion from the Zn+ valence 4s electron. Evidence of spectrally distinct single- and double-acceptor sites are presented for medium-sized clusters, 4 ≤n≤ 7, however for larger clusters, n≥ 8, the hydrogen bonding region is dominated by a broad, unresolved band, indicative of the increased number of second and third coordination sphere ligands. No evidence of a solvated, six-fold coordinated Zn2+ ion/solvated electron pair is present in the spectra.
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Affiliation(s)
- Ethan M Cunningham
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
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15
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Pascher TF, Ončák M, van der Linde C, Beyer MK. Infrared multiple photon dissociation spectroscopy of anionic copper formate clusters. J Chem Phys 2020; 153:184301. [DOI: 10.1063/5.0030034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Tobias F. Pascher
- Institut für Ionen und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Milan Ončák
- Institut für Ionen und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Christian van der Linde
- Institut für Ionen und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Martin K. Beyer
- Institut für Ionen und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
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16
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Pascher TF, Barwa E, van der Linde C, Beyer MK, Ončák M. Photochemical activation of carbon dioxide in Mg +(CO 2)(H 2O) 0,1. Theor Chem Acc 2020; 139:127. [PMID: 32655309 PMCID: PMC7335376 DOI: 10.1007/s00214-020-02640-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/20/2020] [Indexed: 11/25/2022]
Abstract
We combine multi-reference ab initio calculations with UV-VIS action spectroscopy to study photochemical activation of CO2 on a singly charged magnesium ion, [MgCO2(H2O)0,1]+, as a model system for the metal/ligand interactions relevant in CO2 photochemistry. For the non-hydrated species, two separated Mg+ 3s-3p bands are observed within 5.0 eV. The low-energy band splits upon hydration with one water molecule. [Mg(CO2)]+ decomposes highly state-selectively, predominantly via multiphoton processes. Within the low-energy band, CO2 is exclusively lost within the excited state manifold. For the high-energy band, an additional pathway becomes accessible: the CO2 ligand is activated via a charge transfer, with photochemistry taking place on the CO2 - moiety eventually leading to a loss of CO after absorption of a second photon. Upon hydration, already excitation into the first and second excited state leads to CO2 activation in the excited state minimum; however, CO2 predominantly evaporates upon fluorescence or absorption of another photon.
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Affiliation(s)
- Tobias F. Pascher
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Erik Barwa
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Christian van der Linde
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Martin K. Beyer
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
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17
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Bersenkowitsch NK, Ončák M, Heller J, Pascher TF, van der Linde C, Beyer MK. Evidence for lactone formation during infrared multiple photon dissociation spectroscopy of bromoalkanoate doped salt clusters. Phys Chem Chem Phys 2020; 22:12028-12038. [PMID: 32421138 PMCID: PMC7116335 DOI: 10.1039/d0cp00272k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction mechanisms of organic molecules in a salt environment are of
fundamental interest and are potentially relevant for atmospheric chemistry, in
particular sea-salt aerosols. Here, we found evidence for lactone formation upon
infrared multiple photon dissociation (IRMPD) of non-covalent bromoalkanoate
complexes as well as bromoalkanoate embedded in sodium iodide clusters. The
mechanism of lactone formation from bromoalkanoates of different chain lengths
is studied in the gas phase with and without salt environment by a combination
of IRMPD and quantum chemical calculations. IRMPD spectra are recorded in the
833-3846 cmT1 range by
irradiating the clusters with tunable laser systems while they are stored in the
cell of a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer.
The measurements of the binary complex
Br(CH2)mCOOH·Br(CH2)mCOO- for
m = 4 indicate valerolactone formation without salt
environment while lactone formation is hindered for longer chain lengths. When
embedded in sodium iodide clusters, butyrolactone formation from 4-bromobutyrate
seems to take place already during formation of the doped clusters in the
electrospray process, evidenced by the infrared (IR) signature of the lactone.
In contrast, IRMPD spectra of sodium iodide clusters containing 5-bromovalerate
contain signatures for both valerate as well as valerolactone. In both cases,
however, a neutral fragment corresponding to the mass of valerolactone is
eliminated, indicating that ring formation can be activated by IR light in the
salt cluster. Quantum chemical calculations show that already complexation with
one sodium ion significantly increases the barrier for lactone formation for all
chain lengths. IRMPD of sodium iodide clusters doped with neutral bromoalkanoic
acid molecules proceeds by elimination of HI or desorption of the intact acid
molecule from the cluster.
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Affiliation(s)
- Nina K Bersenkowitsch
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
| | - Jakob Heller
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
| | - Tobias F Pascher
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
| | - Christian van der Linde
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
| | - Martin K Beyer
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
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18
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Barwa E, Pascher TF, Ončák M, Linde C, Beyer MK. Aktivierung von Kohlenstoffdioxid an Metallzentren: Entwicklung des Ladungstransfers von Mg
.+
auf CO
2
in [MgCO
2
(H
2
O)
n
]
.+
,
n=
0–8. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202001292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Erik Barwa
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstraße 25 6020 Innsbruck Österreich
| | - Tobias F. Pascher
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstraße 25 6020 Innsbruck Österreich
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstraße 25 6020 Innsbruck Österreich
| | - Christian Linde
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstraße 25 6020 Innsbruck Österreich
| | - Martin K. Beyer
- Institut für Ionenphysik und Angewandte PhysikUniversität Innsbruck Technikerstraße 25 6020 Innsbruck Österreich
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19
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Barwa E, Pascher TF, Ončák M, van der Linde C, Beyer MK. Carbon Dioxide Activation at Metal Centers: Evolution of Charge Transfer from Mg .+ to CO 2 in [MgCO 2 (H 2 O) n ] .+ , n=0-8. Angew Chem Int Ed Engl 2020; 59:7467-7471. [PMID: 32100953 PMCID: PMC7217156 DOI: 10.1002/anie.202001292] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Indexed: 11/06/2022]
Abstract
We investigate activation of carbon dioxide by singly charged hydrated magnesium cations Mg .+(H2O)n, through infrared multiple photon dissociation (IRMPD) spectroscopy combined with quantum chemical calculations. The spectra of [MgCO2(H2O)n].+ in the 1250–4000 cm−1 region show a sharp transition from n=2 to n=3 for the position of the CO2 antisymmetric stretching mode. This is evidence for the activation of CO2 via charge transfer from Mg .+ to CO2 for n≥3, while smaller clusters feature linear CO2 coordinated end‐on to the metal center. Starting with n=5, we see a further conformational change, with CO2.− coordination to Mg2+ gradually shifting from bidentate to monodentate, consistent with preferential hexa‐coordination of Mg2+. Our results reveal in detail how hydration promotes CO2 activation by charge transfer at metal centers.
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Affiliation(s)
- Erik Barwa
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
| | - Tobias F Pascher
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
| | - Christian van der Linde
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
| | - Martin K Beyer
- Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020, Innsbruck, Austria
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20
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Barwa E, Ončák M, Pascher TF, Herburger A, van der Linde C, Beyer MK. Infrared Multiple Photon Dissociation Spectroscopy of Hydrated Cobalt Anions Doped with Carbon Dioxide CoCO 2 (H 2 O) n - , n=1-10, in the C-O Stretch Region. Chemistry 2020; 26:1074-1081. [PMID: 31617628 PMCID: PMC7051846 DOI: 10.1002/chem.201904182] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Indexed: 11/05/2022]
Abstract
We investigate anionic [Co,CO2 ,nH2 O]- clusters as model systems for the electrochemical activation of CO2 by infrared multiple photon dissociation (IRMPD) spectroscopy in the range of 1250-2234 cm-1 using an FT-ICR mass spectrometer. We show that both CO2 and H2 O are activated in a significant fraction of the [Co,CO2 ,H2 O]- clusters since it dissociates by CO loss, and the IR spectrum exhibits the characteristic C-O stretching frequency. About 25 % of the ion population can be dissociated by pumping the C-O stretching mode. With the help of quantum chemical calculations, we assign the structure of this ion as Co(CO)(OH)2 - . However, calculations find Co(HCOO)(OH)- as the global minimum, which is stable against IRMPD under the conditions of our experiment. Weak features around 1590-1730 cm-1 are most likely due to higher lying isomers of the composition Co(HOCO)(OH)- . Upon additional hydration, all species [Co,CO2 ,nH2 O]- , n≥2, undergo IRMPD through loss of H2 O molecules as a relatively weakly bound messenger. The main spectral features are the C-O stretching mode of the CO ligand around 1900 cm-1 , the water bending mode mixed with the antisymmetric C-O stretching mode of the HCOO- ligand around 1580-1730 cm-1 , and the symmetric C-O stretching mode of the HCOO- ligand around 1300 cm-1 . A weak feature above 2000 cm-1 is assigned to water combination bands. The spectral assignment clearly indicates the presence of at least two distinct isomers for n ≥2.
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Affiliation(s)
- Erik Barwa
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Tobias F. Pascher
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Andreas Herburger
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Christian van der Linde
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Martin K. Beyer
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
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21
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Herburger A, Ončák M, Siu C, Demissie EG, Heller J, Tang WK, Beyer MK. Infrared Spectroscopy of Size-Selected Hydrated Carbon Dioxide Radical Anions CO 2 .- (H 2 O) n (n=2-61) in the C-O Stretch Region. Chemistry 2019; 25:10165-10171. [PMID: 31132183 PMCID: PMC6771497 DOI: 10.1002/chem.201901650] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Indexed: 11/08/2022]
Abstract
Understanding the intrinsic properties of the hydrated carbon dioxide radical anions CO2 .- (H2 O)n is relevant for electrochemical carbon dioxide functionalization. CO2 .- (H2 O)n (n=2-61) is investigated by using infrared action spectroscopy in the 1150-2220 cm-1 region in an ICR (ion cyclotron resonance) cell cooled to T=80 K. The spectra show an absorption band around 1280 cm-1 , which is assigned to the symmetric C-O stretching vibration νs . It blueshifts with increasing cluster size, reaching the bulk value, within the experimental linewidth, for n=20. The antisymmetric C-O vibration νas is strongly coupled with the water bending mode ν2 , causing a broad feature at approximately 1650 cm-1 . For larger clusters, an additional broad and weak band appears above 1900 cm-1 similar to bulk water, which is assigned to a combination band of water bending and libration modes. Quantum chemical calculations provide insight into the interaction of CO2 .- with the hydrogen-bonding network.
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Affiliation(s)
- Andreas Herburger
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Milan Ončák
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Chi‐Kit Siu
- Department of ChemistryCity University of Hong Kong83 Tat Chee AvenueKowloon Tong, Hong Kong SARP. R. China
| | - Ephrem G. Demissie
- Department of ChemistryCity University of Hong Kong83 Tat Chee AvenueKowloon Tong, Hong Kong SARP. R. China
| | - Jakob Heller
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
| | - Wai Kit Tang
- Department of ChemistryCity University of Hong Kong83 Tat Chee AvenueKowloon Tong, Hong Kong SARP. R. China
| | - Martin K. Beyer
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020InnsbruckAustria
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