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McGee CJ, McGinnis KR, Jarrold CC. Anion Photoelectron Imaging Spectroscopy of C 6HF 5-, C 6F 6-, and the Absence of C 6H 2F 4. J Phys Chem A 2023; 127:8556-8565. [PMID: 37816145 DOI: 10.1021/acs.jpca.3c04016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/12/2023]
Abstract
Substituents have a profound effect on the electronic structure of the benzene molecule. In this paper, we present new photoelectron spectra of the C5HF5- molecular anion, to test predictions [ Int. J. Quant. Chem. 2017, 188, e25504] that pentafluorobenzene has a positive electron affinity, as hexafluorobenzene was already known to have. The PE spectrum of C6HF5- exhibits a broad and vibrationally unresolved band due to significant differences between the structure of the anion and the neutral. The vertical detachment energy (VDE) of C5HF5- is determined to be 1.33 ± 0.05 eV, and the lowest binding energy at which the signal is observed is 0.53 ± 0.05 eV, which, if taken as the electron affinity, is in good agreement with the computed value. In addition, we attempted to generate intact C6H2F4- molecular ions using the 1,2,3,4-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene, and 1,2,4,5-tetrafluorobenzene precursors, as tetrafluorobenzene was predicted to have a near-zero but marginally positive electron affinity. Using a photoemission anion source, we were not able to produce the intact tetrafluorobenzene anion. Density functional theory calculations support a more detailed discussion of the impact of fluorine substitution on the electronic structure of these species.
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Affiliation(s)
- Conor J McGee
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Kristen Rose McGinnis
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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2
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Jarrold CC. Probing Anion-Molecule Complexes of Atmospheric Relevance Using Anion Photoelectron Detachment Spectroscopy. ACS PHYSICAL CHEMISTRY AU 2022; 3:17-29. [PMID: 36718261 PMCID: PMC9881448 DOI: 10.1021/acsphyschemau.2c00060] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/08/2022] [Accepted: 12/09/2022] [Indexed: 01/01/2023]
Abstract
Bimolecular reaction and collision complexes that drive atmospheric chemistry and contribute to the absorption of solar radiation are fleeting and therefore inherently challenging to study experimentally. Furthermore, primary anions in the troposphere are short lived because of a complicated web of reactions and complex formation they undergo, making details of their early fate elusive. In this perspective, the experimental approach of photodetaching mass-selected anion-molecule complexes or complex anions, which prepares neutrals in various vibronic states, is surveyed. Specifically, the application of anion photoelectron spectroscopy along with photoelectron-photofragment coincidence spectroscopy toward the study of collision complexes, complex anions in which a partial covalent bond is formed, and radical bimolecular reaction complexes, with relevance in tropospheric chemistry, will be highlighted.
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Benitez Y, Nguyen TL, Parsons AJ, Stanton JF, Continetti RE. Probing the Exit Channel of the OH + CH 3OH → H 2O + CH 3O Reaction by Photodetachment of CH 3O -(H 2O). J Phys Chem Lett 2022; 13:142-148. [PMID: 34962408 DOI: 10.1021/acs.jpclett.1c03568] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Transition state dynamics of bimolecular reactions can be probed by photodetachment of a precursor anion when the Franck-Condon region of the corresponding neutral potential energy surface is near a saddle point. In this study, photodetachment of anions at m/z = 49 enabled investigation of the exit channel of the OH + CH3OH → H2O + CH3O reaction using photoelectron-photofragment coincidence spectroscopy. High-level coupled-cluster calculations of the stationary points on the anion surface show that the methoxide-water cluster CH3O-(H2O) is the stable minimum on the anion surface. Photodetachment at a 3.20 eV photon energy leads to long-lived H2O(CH3O) complexes and H2O + CH3O products consistent with both direct dissociative photodetachment and resonance mediated processes on the neutral surface. The partitioning of total kinetic energy in the system indicates that water stretch and bend excitation is induced in dissociative photodetachment and evidence for long-lived complexes consistent with vibrational Feshbach resonances is reported.
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Affiliation(s)
- Yanice Benitez
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Thanh Lam Nguyen
- Quantum Theory Project, Department of Chemistry and Physics, University of Florida, Gainesville, Florida 32611, United States
| | - Austin J Parsons
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - John F Stanton
- Quantum Theory Project, Department of Chemistry and Physics, University of Florida, Gainesville, Florida 32611, United States
| | - Robert E Continetti
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
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Sanov A. Intermolecular interactions in cluster anions. INT REV PHYS CHEM 2021. [DOI: 10.1080/0144235x.2021.1983292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Andrei Sanov
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ, USA
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Yang B, Ding K, Li T, Qu C, Zhu L, Ge Z. Experimental Observation and Energy Performance Calculations of Potential Oxidants O4−/0 and O6−/0 Clusters. FIREPHYSCHEM 2021. [DOI: 10.1016/j.fpc.2021.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Benitez Y, Parsons AJ, Lunny KG, Continetti RE. Dissociative Photodetachment Dynamics of the OH -(C 2H 4) Anion Complex. J Phys Chem A 2021; 125:4540-4547. [PMID: 34030440 DOI: 10.1021/acs.jpca.1c01835] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Photoelectron-photofragment coincidence (PPC) measurements on OH-(C2H4) anions at a photon energy of 3.20 eV revealed stable and dissociative photodetachment product channels, OH-C2H4 + e- and OH + C2H4 + e-, respectively. The main product channel observed was dissociation to the reactants (>67%), OH + C2H4 (v = 0, 1, 2) + e-, where vibrational excitation in the C-H stretching modes of the C2H4 photofragments corresponds to a minor channel. The low kinetic energy release (KER) of the dissociating fragments is consistent with weak repulsion between the OH + C2H4 reactants near the transition state as well as the partitioning of energy into rotation of the dissociation products. An impulsive model was used to account for rotational energy partitioning in the dissociative photodetachment (DPD) process and showed good agreement with the experimental results. The low KER of the dissociating fragments and the similarities in the photoelectron spectra between stable and dissociative events support a mechanism involving the van der Waals complex formed upon photodetachment of OH-(C2H4) as an intermediate in the dominant OH + C2H4 + e- dissociative channel.
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Affiliation(s)
- Yanice Benitez
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Austin J Parsons
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Katharine G Lunny
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Robert E Continetti
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
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Benitez Y, Lu D, Lunny KG, Li J, Guo H, Continetti RE. Photoelectron–Photofragment Coincidence Studies on the Dissociation Dynamics of the OH–CH4 Complex. J Phys Chem A 2019; 123:4825-4833. [DOI: 10.1021/acs.jpca.9b02441] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yanice Benitez
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Dandan Lu
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China
| | - Katharine G. Lunny
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Jun Li
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China
- Institut für Physikalische Chemie, Theoretische Chemie, Universität Göttingen, Göttingen 37077, Germany
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
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Dauletyarov Y, Wallace AA, Blackstone CC, Sanov A. Photoelectron Spectroscopy of Biacetyl and Its Cluster Anions. J Phys Chem A 2019; 123:4158-4167. [PMID: 31017789 DOI: 10.1021/acs.jpca.9b01302] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Photoelectron spectroscopy of the biacetyl (dimethylglyoxal) anion reveals the properties of the ground singlet and lowest triplet electronic states of the neutral biacetyl (BA) molecule. Due to the broad and congested nature of the singlet transition, which peaks at a vertical detachment energy VDE = 1.12(5) eV, only an upper bound of the adiabatic electron affinity of BA could be determined: EA(BA) < 0.7 eV. A narrower and more structured triplet band peaking at VDE = 3.17(2) eV reveals the adiabatic electron binding energy of the triplet to be 3.05(2) eV. These results are in good agreement with ab initio (coupled-cluster) calculations. The lowest-energy structures of the anion, singlet, and triplet states of biacetyl are characterized by different orientations of the methyl groups within the molecular frame. In the ground singlet state of neutral BA, the methyl torsion is offset by ∼60° compared to that of the anion, while in the triplet the methyl orientation is similar to that of the anion. Photoelectron spectra of the cluster anions reveal that the intermolecular interactions in the homogeneously solvated (BA) n- clusters are significantly stronger than the interactions of BA- with N2O or even of BA- with H2O. To account for these observations, π-π bonded structures of the dimer and trimer anions of biacetyl are proposed based on density-functional theory calculations. The analysis of the proposed structures indicates that the negative charge in the (BA) n- cluster anions, at least in the dimer and the trimer, is significantly delocalized between all BA moieties present and there is a significant degree of covalent bonding within the cluster.
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Affiliation(s)
- Yerbolat Dauletyarov
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
| | - Adam A Wallace
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
| | - Christopher C Blackstone
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
| | - Andrei Sanov
- Department of Chemistry and Biochemistry , The University of Arizona , Tucson , Arizona 85721 , United States
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Gibbard JA, Shin AJ, Castracane E, Continetti RE. A high beam energy photoelectron-photofragment coincidence spectrometer for complex anions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:123304. [PMID: 30599593 DOI: 10.1063/1.5074112] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 11/20/2018] [Indexed: 06/09/2023]
Abstract
A new high beam energy photoelectron-photofragment coincidence (PPC) spectrometer is described that allows acceleration of heavy anions (>100 amu) to energies in the tens of keV using a linear accelerator (LINAC). High beam energies result in more efficient detection of the neutral photofragments produced via dissociative photodetachment (DPD) of the parent anion and increase the mass range that can be studied with PPC spectroscopy. The novel experimental setup couples an electrospray ionization (ESI) source and a hexapole accumulation trap with a 10-stage LINAC to give a kinematically complete measurement of the dissociation dynamics for heavier anions. ESI dramatically increases the range of anions that can be studied by PPC spectroscopy to include multiply charged anions and larger, more complex molecular ions important in biological, atmospheric, and combustion processes. A radiofrequency buffer-gas-cooled hexapole trap is used to accumulate sufficient ion density for single-shot coincidence measurements and thermalize the anions to room temperature. The photoelectron and up to three neutral fragments resulting from DPD are recorded in coincidence using time and position sensitive detectors. This novel experimental setup is characterized by studying the photodetachment of I-, and the DPD of I 2 - and the oxalate anion C2O4H- at beam energies of 11 keV, 16 keV, and 21 keV.
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Affiliation(s)
- J A Gibbard
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Dr, La Jolla, San Diego, California 92093-0340, USA
| | - A J Shin
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Dr, La Jolla, San Diego, California 92093-0340, USA
| | - E Castracane
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Dr, La Jolla, San Diego, California 92093-0340, USA
| | - R E Continetti
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Dr, La Jolla, San Diego, California 92093-0340, USA
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10
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Suits AG. Invited Review Article: Photofragment imaging. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:111101. [PMID: 30501356 DOI: 10.1063/1.5045325] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 10/25/2018] [Indexed: 06/09/2023]
Abstract
Photodissociation studies in molecular beams that employ position-sensitive particle detection to map product recoil velocities emerged thirty years ago and continue to evolve with new laser and detector technologies. These powerful methods allow application of tunable laser detection of single product quantum states, simultaneous measurement of velocity and angular momentum polarization, measurement of joint product state distributions for the detected and undetected products, coincident detection of multiple product channels, and application to radicals and ions as well as closed-shell molecules. These studies have permitted deep investigation of photochemical dynamics for a broad range of systems, revealed new reaction mechanisms, and addressed problems of practical importance in atmospheric, combustion, and interstellar chemistry. This review presents an historical overview, a detailed technical account of the range of methods employed, and selected experimental highlights illustrating the capabilities of the method.
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Affiliation(s)
- Arthur G Suits
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
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11
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Shen BB, Benitez Y, Lunny KG, Continetti RE. Internal energy dependence of the photodissociation dynamics of O3− using cryogenic photoelectron-photofragment coincidence spectroscopy. J Chem Phys 2017; 147:094307. [PMID: 28886639 DOI: 10.1063/1.4986500] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ben B. Shen
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Drive, La Jolla, San Diego, California 92093, USA
| | - Yanice Benitez
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Drive, La Jolla, San Diego, California 92093, USA
| | - Katharine G. Lunny
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Drive, La Jolla, San Diego, California 92093, USA
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California, 9500 Gilman Drive, La Jolla, San Diego, California 92093, USA
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Patros KM, Mann JE, Jarrold CC. Photoelectron Imaging Spectra of O 2-·VOC and O 4-·VOC Complexes. J Phys Chem A 2016; 120:7828-7838. [PMID: 27648607 DOI: 10.1021/acs.jpca.6b07107] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The anion photoelectron imaging spectra of O2-·VOC and O4-·VOC (VOC = hexane, isoprene, benzene, and benzene-d6) complexes measured using 3.49 eV photon energy, along with the results of ab initio and density functional theory results are reported and analyzed. Photodetachment of these anionic complexes accesses neutrals that model collision complexes, offering a probe of the effects of symmetry-breaking collision events on the electronic structure of normally transparent neutral molecules. The energies of O2-·VOC spectral features compared to the bare O2- indicate that photodetachment of the anion accesses a modestly repulsive region of the O2-VOC potential energy surface, with subtle VOC dependence on the relative energies of the O2 (X 3Σg-)·VOC ground state and O2 (a 1Δg)·VOC excited state. In contrast, a significantly higher intensity of the transition to the O2 (a 1Δg)·VOC excited state relative to the O2 (X 3Σg-)·VOC ground state is observed for VOC = benzene, with a less pronounced effect observed for VOC = isoprene. Similar spectral effects are observed in the O4-·benzene and O4-·isoprene PE spectra. Several explanations are considered, with involvement of a temporary anion state emerging as the most plausible.
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Affiliation(s)
- Kellyn M Patros
- Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Jennifer E Mann
- Physical Electronics , 18725 Lake Drive East, Chanhassen, Minnesota 55317, United States
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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Hu Q, Song H, Johnson CJ, Li J, Guo H, Continetti RE. Imaging a multidimensional multichannel potential energy surface: Photodetachment of H−(NH3) and NH4−. J Chem Phys 2016; 144:244311. [DOI: 10.1063/1.4954187] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Qichi Hu
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, USA
| | - Hongwei Song
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Christopher J. Johnson
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, USA
| | - Jun Li
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, USA
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Mann JE, Troyer ME, Jarrold CC. Photoelectron imaging and photodissociation of ozonide in O3(-)⋅(O2)n (n = 1-4) clusters. J Chem Phys 2015; 142:124305. [PMID: 25833577 DOI: 10.1063/1.4916048] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The photoelectron images of O3 (-) and O3 (-) ⋅ (O2)n (n = 1-4) have been measured using 3.49 eV photon energy. The spectra exhibit several processes, including direct photodetachment and photodissociation with photodetachment of O(-) photofragments. Several spectra also exhibit autodetachment of vibrationally excited O2 (-) photofragments. Comparison of the bare O3 (-) photoelectron spectra to that of the complexes shows that the O3 (-) core is preserved upon clustering with several O2 molecules, though subtle changes in the Franck-Condon profile of the ground state photodetachment transition suggest some charge transfer from O3 (-) to the O2 molecules. The electron affinities of the complexes increase by less than 0.1 eV with each additional O2 molecule, which is comparable to the corresponding binding energy [K. Hiraoka, Chem. Phys. 125, 439-444 (1988)]. The relative intensity of the photofragment O(-) detachment signal to the O3 (-) ⋅ (O2)n direct detachment signal increases with cluster size. O2 (-) autodetachment signal is only observed in the O3 (-), O3 (-) ⋅ (O2)3, and O3 (-) ⋅ (O2)4 spectra, suggesting that the energy of the dissociative state also varies with the number of O2 molecules present in the cluster.
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Affiliation(s)
- Jennifer E Mann
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 40405, USA
| | - Mary E Troyer
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 40405, USA
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 40405, USA
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Khuseynov D, Goebbert DJ, Sanov A. Oxygen cluster anions revisited: solvent-mediated dissociation of the core O4(-) anion. J Chem Phys 2012; 136:094312. [PMID: 22401445 DOI: 10.1063/1.3691104] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electronic structure and photochemistry of the O(2n)(-)(H(2)O)(m), n = 1-6, m = 0-1 cluster anions is investigated at 532 nm using photoelectron imaging and photofragment mass-spectroscopy. The results indicate that both pure oxygen clusters and their hydrated counterparts with n ≥ 2 form an O(4)(-) core. Fragmentation of these clusters yields predominantly O(2)(-) and O(2)(-)·H(2)O anionic products, with the addition of O(4)(-) fragments for larger parent clusters. The fragment autodetachment patterns observed for O(6)(-) and larger O(2n)(-) species, as well as some of their hydrated counterparts, indicate that the corresponding O(2)(-) fragments are formed in excited vibrational states (v ≥ 4). Yet, surprisingly, the unsolvated O(4)(-) anion itself does not show fragment autodetachment at 532 nm. It is hypothesized that the vibrationally excited O(2)(-) is formed in the intra-cluster photodissociation of the O(4)(-) core anion via a charge-hopping electronic relaxation mechanism mediated by asymmetric solvation of the nascent photofragments: O(4)(-) → O(2)(-)(X(2)Π(g)) + O(2)(a(1)Δ(g)) → O(2)(X(3)Σ(g)(-)) + O(2)(-)(X(2)Π(g)). This process depends on the presence of solvent molecules and leads to vibrationally excited O(2)(-)(X(2)Π(g)) products.
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Affiliation(s)
- Dmitry Khuseynov
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, USA
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Goebbert DJ, Sanov A. Photodetachment, photofragmentation, and fragment autodetachment of [O[sub 2n](H[sub 2]O)[sub m]][sup −] clusters: Core-anion structures and fragment energy partitioning. J Chem Phys 2009. [DOI: 10.1063/1.3224135] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Lu Z, Oakman JE, Hu Q, Continetti RE. Photoelectron-photofragment angular correlations in the dissociative photodetachment of HOCO−. Mol Phys 2008. [DOI: 10.1080/00268970801971376] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Kang C, Troyer JL, Robertson EM, Rothgeb DW, Hossain E, Wyrwas RB, Parmenter CS, Jarrold CC. Solvation of O(2)(-) and O(4)(-) by p-difluorobenzene and p-xylene studied by photoelectron spectroscopy. J Chem Phys 2008; 128:104309. [PMID: 18345890 DOI: 10.1063/1.2838849] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Anion photoelectron spectra of the O(2)(-) . arene and O(4)(-) . arene complexes with p-xylene and p-difluorobenzene are presented and analyzed with the aid of calculations on the anions and corresponding neutrals. Relative to the adiabatic electron affinity of O(2), the O(2)(-) . arene spectra are blueshifted by 0.75-1 eV. Solvation energy alone does not account for this shift, and it is proposed that a repulsive portion of the neutral potential energy surface is accessed in the detachment, resulting in dissociative photodetachment. O(2)(-) is found to interact more strongly with the p-difluorobenzene than the p-xylene. The binding motif involves the O(2)(-) in plane with the arene, interacting via electron donation along nearby C-H bonds. A peak found at 4.36(2) eV in the photoelectron spectrum of O(2)(-) . p-difluorobenzene (p-DFB) is tentatively attributed to the charge transfer state, O(2)(-) . p-DFB(+). Spectra of O(4)(-) . arene complexes show less blueshift in electron binding energy relative to the spectrum of bare O(4)(-), which itself undergoes dissociative photodetachment. The striking similarity between the profiles of the O(4)(-) . arene complexes with the O(4)(-) spectrum suggests that the O(4)(-) molecule remains intact upon complex formation, and delocalization of the charge across the O(4)(-) molecule results in similar structures for the anion and neutral complexes.
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Affiliation(s)
- Cheolhwa Kang
- Department of Chemistry, Indiana University, Bloomington, IN 47405, USA
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Affiliation(s)
- M. Shane Bowen
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340
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Li W, Poisson L, Peterka DS, Ahmed M, Lucchese RR, Suits AG. Dissociative photoionization dynamics in ethane studied by velocity map imaging. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)00712-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Clements TG, Continetti RE, Francisco JS. Exploring the OH+CO→H+CO2 potential surface via dissociative photodetachment of (HOCO)−. J Chem Phys 2002. [DOI: 10.1063/1.1505439] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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23
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Clements TG, Continetti RE. Four-body reaction dynamics: complete correlated fragment measurement of the dissociative photodetachment dynamics of O(-)(8). PHYSICAL REVIEW LETTERS 2002; 89:033005. [PMID: 12144391 DOI: 10.1103/physrevlett.89.033005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2002] [Indexed: 05/23/2023]
Abstract
The four-body dissociative photodetachment (DPD) dynamics of O-8 were studied using photoelectron photofragment coincidence (PPC) spectroscopy. All four neutral photofragments were measured in coincidence with the photodetached electron, yielding a five-body kinematically complete experiment. Velocity and angular correlations for DPD of O(-)(8) are presented and compared to those for O(-)(6). The DPD dynamics and energetics of O(-)(8).are found to be similar to those of O-4 and O-6 implying that the additional solvating O(2) molecules act essentially as spectators, but exhibit inequivalent kinematic behavior implying asymmetric solvation.
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Affiliation(s)
- Todd G Clements
- Department of Chemistry and Biochemistry, University of California-San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, USA
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24
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Zhai HJ, Yang X, Wang XB, Wang LS, Elliott B, Boldyrev AI. In search of covalently bound tetra- and penta-oxygen species: a photoelectron spectroscopic and Ab initio investigation of MO4- and MO5- (M = Li, Na, K, Cs). J Am Chem Soc 2002; 124:6742-50. [PMID: 12047195 DOI: 10.1021/ja020097k] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although neutral and ionic O4(0/-/+) species have been observed experimentally and considered for energetic materials, O4(2-) and O5(2-) dianions have not yet been explored. O4(2-) is valent isoelectronic to the well-known ClO3- and SO3(2-) anions, and O5(2-) is valent isoelectronic to ClO4- and SO4(2-). All are stable, common anions in solutions and inorganic salts. In this article, we explore the possibility of making covalently bound O4(2-) and O5(2-) species stabilized in the forms of M+O4(2-) and M+O5(2-) (M = Li, Na, K, Cs) in the gas phase. Laser vaporization experiments using M-containing targets and an O2-seeded carrier gas yielded very intense mass peaks corresponding to MO4- and MO5-. To elucidate the structure and bonding of the newly observed MO4- and MO5- species, we measured their photoelectron spectra and then compared them with ab initio calculations and the spectra of ClO3-, Na+SO3(2-), ClO4-, and Na+SO4(2-). Careful analyses of the experimental and ab initio results showed, however, that the observed species are of the forms, O2-M+O2- and O2-M+O3-. The more interesting M+O4(2-) and M+O5(2-) species were found to be higher-energy isomers, but they are true minima on the potential energy surfaces, which suggests that it might be possible to synthesize bulk materials containing covalently bound tetra- and pentatomic oxygen building blocks.
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Affiliation(s)
- Hua-Jin Zhai
- Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99352, USA
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25
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Li R, Continetti RE. Studies of the Excited State Dynamics of N2O2 by Dissociative Photodetachment of N2O2-. J Phys Chem A 2002. [DOI: 10.1021/jp013330u] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Runjun Li
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340
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26
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Liang B, Andrews L. Infrared spectra of cis- and trans-peroxynitrite anion, OONO-, in solid argon. J Am Chem Soc 2001; 123:9848-54. [PMID: 11583548 DOI: 10.1021/ja0114299] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The peroxynitrite anion, of vast importance in biochemistry, is formed in vivo from the reaction of NO and O(-2). Laser ablation of 10 different metal targets with concurrent 7 K codeposition of NO/Ar and O(2)/Ar mixtures gives new metal-independent infrared bands at 1458.3 and 806.1 cm(-)(1), and at 1433.3 and 983.2 cm(-1), in addition to known O(-4) and (NO)(-2) absorptions. The new bands are not observed with CCl(4) added to capture electrons or in O(2) and NO experiments without laser ablation to produce electrons, which identifies new product anions. Based on (15)NO and (18)O(2) isotopic shifts, splitting patterns in mixed isotopic experiments, and comparison with DFT isotopic frequency calculations, the former absorptions are assigned to cis-OONO-, and the latter pair to trans-OONO-, which are isolated from metal cations trapped elsewhere in the matrix. The cis- and trans-peroxynitrite anion isomers are probably formed via the ion-molecule reaction between O(-2)and NO: the O(-2) anion, made by the capture of ablated electrons, is attested by the observation of O(-4). cis- and trans-OONO- are reversibly photoisomerized by visible and near-UV radiation. Collisional stabilization of the OONO- ion-molecule dimer complex during formation of the solid argon matrix appears to be crucial.
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Affiliation(s)
- B Liang
- Department of Chemistry, University of Virginia, P.O. Box 400319, Charlottesville, VA 22904-4319, USA
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27
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Clements TG, Continetti RE. Predissociation dynamics of formyloxyl radical studied by the dissociative photodetachment of HCO2−/DCO2−+hν→H/D+CO2+e−. J Chem Phys 2001. [DOI: 10.1063/1.1404143] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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28
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Abstract
The application of coincidence techniques to the study of the reaction dynamics of isolated molecules is reviewed. Coincidence spectroscopy is a powerful approach for carrying out a number of measurements. At its most basic level, coincidence techniques can identify the source of a specific signal, as in the well-known photoelectron-photoion coincidence approach used for several years. By carrying out coincidence experiments in an increasingly differential manner, correlated energy and angular distributions of reaction products may be recorded. Completely energy- and angle-resolved measurements of photoelectrons and ionic or neutral products can reveal molecular-frame photoelectron and photofragment angular distributions and aid in the characterization of dissociative states of molecules and ions. Recent work in this area is reviewed, including examples from studies of dissociative photodetachment, dissociative photoionization, time-resolved studies of dissociative photoionization, and three-body dissociation processes.
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Affiliation(s)
- R E Continetti
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, California 92093-0314, USA.
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29
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Alconcel LS, Deyerl HJ, DeClue M, Continetti RE. Dissociation Dynamics and Stability of Cyclic Alkoxy Radicals and Alkoxide Anions. J Am Chem Soc 2001. [DOI: 10.1021/ja0042581] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Leah S. Alconcel
- Contribution from the Department of Chemistry and Biochemistry, 0314, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0314
| | - Hans-Jürgen Deyerl
- Contribution from the Department of Chemistry and Biochemistry, 0314, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0314
| | - Michael DeClue
- Contribution from the Department of Chemistry and Biochemistry, 0314, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0314
| | - Robert E. Continetti
- Contribution from the Department of Chemistry and Biochemistry, 0314, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0314
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30
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Li R, Alconcel LNS, Continetti RE. Dissociative photodetachment of SO2·SO2−: evidence for the S–O bound dimer. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)00033-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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31
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Luong AK, Clements TG, Sowa Resat M, Continetti RE. Energetics and dissociative photodetachment dynamics of superoxide–water clusters: O2−(H2O)n, n=1–6. J Chem Phys 2001. [DOI: 10.1063/1.1342221] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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32
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Aquino AJA, Taylor PR, Walch SP. Structure, properties, and photodissociation of O4−. J Chem Phys 2001. [DOI: 10.1063/1.1288379] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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