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Parsons BF, Hulce MR, Ackerman JR, Reardon KA, Pappas ES, Kettler LE. Ultraviolet Excitation of M-O 2 (M = Phenalenone, Fluorenone, Pyridine, & Acridine) Complexes Resulting in 1O 2. J Phys Chem A 2024; 128:2971-2981. [PMID: 38579334 DOI: 10.1021/acs.jpca.4c00143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
In our experiment, a trace amount of an organic molecule (M = 1H-phenalen-1-one, 9-fluorenone, pyridine, or acridine) was seeded into a gas mix consisting of 3% O2 with a rare gas buffer (He or Ar) and then supersonically expanded. We excited the resulting molecular beam with ultraviolet light at either 355 nm (1H-phenalen-1-one, 9-fluorenone, or acridine) or 266 nm (pyridine) and used resonance enhanced multiphoton ionization (REMPI) spectroscopy to probe for the formation of O2 in the a-1Δg state, 1O2. For all systems, the REMPI spectra demonstrate that ultraviolet excitation results in the formation of 1O2 and the oxygen product is confirmed to be in the ground vibrational state and with an effective rotational temperature below 80 K. We then recorded the velocity map ion image of the 1O2 product. From the ion images, we determined the center-of-mass translational energy distribution, P(ET), assuming photodissociation of a bimolecular M-O2 complex. We also report results from electronic structure calculations that allow for a determination of the M-O2 ground state binding energy. We use the complex binding energy, the energy to form 1O2, and the adiabatic triplet energy for each organic molecule to determine the available energy following photodissociation. For dissociation of a bimolecular complex, this available energy may be partitioned into either center-of-mass recoil or internal degrees of freedom of the organic moiety. We use the available energy to generate a Prior distribution, which predicts statistical energy partitioning during dissociation. For low available energies, less than 0.2 eV, we find that the statistical prediction is in reasonable agreement with the experimental observations. However, at higher available energies, the experimental distribution is biased to lower center-of-mass kinetic energies compared with the statistical prediction, which suggests the complex undergoes vibrational predissociation.
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Affiliation(s)
- Bradley F Parsons
- Department of Chemistry and Biochemistry 2500 California Plaza, Creighton University, Omaha, Nebraska 68178, United States
| | - Martin R Hulce
- Department of Chemistry and Biochemistry 2500 California Plaza, Creighton University, Omaha, Nebraska 68178, United States
| | - John R Ackerman
- Department of Chemistry and Biochemistry 2500 California Plaza, Creighton University, Omaha, Nebraska 68178, United States
| | - Kylie A Reardon
- Department of Chemistry and Biochemistry 2500 California Plaza, Creighton University, Omaha, Nebraska 68178, United States
| | - Emerson S Pappas
- Department of Chemistry and Biochemistry 2500 California Plaza, Creighton University, Omaha, Nebraska 68178, United States
| | - Lauren E Kettler
- Department of Chemistry and Biochemistry 2500 California Plaza, Creighton University, Omaha, Nebraska 68178, United States
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Semionova VV, Pozdnyakov IP, Grivin VP, Eltsov IV, Vasilchenko DB, Polyakova EV, Melnikov AA, Chekalin SV, Wang L, Glebov EM. Primary processes in photophysics and photochemistry of a potential light-activated anti-cancer dirhodium complex. Photochem Photobiol Sci 2024; 23:153-162. [PMID: 38066379 DOI: 10.1007/s43630-023-00509-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 11/09/2023] [Indexed: 02/02/2024]
Abstract
Photophysics and photochemistry of a potential light-activated cytotoxic dirhodium complex [Rh2(µ-O2CCH3)2(bpy)(dppz)](O2CCH3)2, where bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine (Complex 1 or Rh2) in aqueous solutions was studied by means of stationary photolysis and time-resolved methods in time range from hundreds of femtoseconds to microseconds. According to the literature, Complex 1 demonstrates both oxygen-dependent (due to singlet oxygen formation) and oxygen-independent cytotoxicity. Photoexchange of an acetate ligand to a water molecule was the only observed photochemical reaction, which rate was increased by oxygen removal from solutions. Photoexcitation of Complex 1 results in the formation of the lowest triplet electronic excited state, which lifetime is less than 10 ns. This time is too short for diffusion-controlled quenching of the triplet state by dissolved oxygen resulting in 1O2 formation. We proposed that singlet oxygen is produced by photoexcitation of weakly bound van der Waals complexes [Rh2…O2], which are formed in solutions. If this is true, no oxygen-independent light-induced cytotoxicity of Complex 1 exists. Residual cytotoxicity deaerated solutions are caused by the remaining [Rh2…O2] complexes.
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Affiliation(s)
- Veronica V Semionova
- Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Ivan P Pozdnyakov
- Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Vjacheslav P Grivin
- Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Ilia V Eltsov
- Novosibirsk State University, Novosibirsk, Russian Federation
| | - Danila B Vasilchenko
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Evgeniya V Polyakova
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation
| | - Alexei A Melnikov
- Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow, Russian Federation
- Department of Physics, High School of Economy, Moscow, Russian Federation
| | - Sergei V Chekalin
- Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow, Russian Federation
| | - Lei Wang
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Evgeni M Glebov
- Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russian Federation.
- Novosibirsk State University, Novosibirsk, Russian Federation.
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3
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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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Parsons BF, Szpunar DE. Investigation of O 2-X (X = Pyrrole or Pyridine) Cluster Photodissociation Near 226 nm. J Phys Chem A 2020; 124:10152-10161. [PMID: 33232146 DOI: 10.1021/acs.jpca.0c09323] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have recorded the O-atom velocity map photofragment ion images resulting from the photodissociation of O2-pyrrole and O2-pyridine clusters near 226 nm. To record the images, the O-atom photoproduct was state-selectively ionized and projected onto a two-dimensional (2D) position-sensitive detector. The resulting ion images from the clusters show evidence for three dissociation pathways. In the images from either cluster, we observe an isotropic process with kinetic energy near the one-photon limit, which is due to dissociation of the cluster into molecular subunits followed by secondary dissociation of molecular oxygen. Both O2-pyrrole and O2-pyridine also show a low kinetic energy process that appears to be isotropic in nature. This low kinetic energy process likely results from dissociation of the cluster resulting in significant internal energy in the organic fragment followed by secondary dissociation of O2. Finally, our ion images for O2-pyrrole show O atoms resulting from a two-photon dissociation channel, which has been previously attributed to the formation and subsequent photodissociation of excited O2 (a 1Δg). At similar laser intensities, O2-pyridine does not show significant dissociation through the channel producing O2 (a 1Δg); however, this channel shows a laser intensity dependence for O2-pyridine.
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Affiliation(s)
- Bradley F Parsons
- Department of Chemistry, Creighton University, 2500 California Plaza, Omaha, Nebraska 68178, United States
| | - David E Szpunar
- Department of Chemistry, University of Wisconsin-Stevens Point, 2101 Fourth Avenue, Stevens Point, Wisconsin 54481, United States
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6
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Pyryaeva AP, Ershov KS, Kochubei SA, Baklanov AV. Singlet Oxygen Generation via UV-A, -B, and -C Photoexcitation of Isoprene-Oxygen (C 5H 8-O 2) Encounter Complexes in the Gas Phase. J Phys Chem A 2020; 124:8469-8477. [PMID: 32986424 DOI: 10.1021/acs.jpca.0c07509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The formation of singlet oxygen 1O2 provided by the photoexcitation of the encounter complexes of isoprene with oxygen (C5H8-O2) in the gas phase within the spectral region 253.5-355 nm has been observed at the elevated pressure of oxygen. Singlet oxygen has been detected with its NIR luminescence centered near 1.27 μm. The photogeneration of 1O2 is found to be a one-photon process. In the UV-C region (253-278 nm) the quantum yield of 1O2 is measured. This yield of 1O2 is governed mainly by photoexcitation of O2 molecules to the Herzberg III (3Δu) state via enhanced absorption by C5H8-O2 collision complexes. So excited triplet O2 gives rise to singlet oxygen because of triplet-triplet annihilation in the collisions with unexcited O2 molecules. In the UV-B (308 nm) region the appearance of 1O2 is attributed to the excitation of a double spin-flip (DSF) transition in complex C5H8-O2. In the UV-A region (355 nm) besides DSF the O2-assisted T1 ← S0 excitation of isoprene to the triplet state takes place, which is a sensitizer of 1O2 formation. The contribution of the encounter complexes C5H8-O2 to the production of singlet oxygen and to the lifetime of isoprene in the Earth's troposphere are estimated.
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Affiliation(s)
- Alexandra P Pyryaeva
- Voevodsky Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090, Russia.,Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russia
| | - Kirill S Ershov
- Voevodsky Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090, Russia.,Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russia
| | - Sergei A Kochubei
- Institute of Semiconductor Physics, ac. Lavrent'yev ave., 13, Novosibirsk 630090, Russia
| | - Alexey V Baklanov
- Voevodsky Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090, Russia.,Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russia
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7
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Baklanov AV, Parker DH. Weakly Bound Environment of Molecular Oxygen as a Catalyst of Photooxidation. KINETICS AND CATALYSIS 2020. [DOI: 10.1134/s0023158420020019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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REMPI detection of singlet oxygen 1O2 arising from UV-photodissociation of van der Waals complex isoprene-oxygen C5H8-O2. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2017.12.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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9
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Patros KM, Mann JE, Jarrold CC. O 2-·[Polar VOC] Complexes: H-Bonding versus Charge-Dipole Interactions, and the Noninnocence of Formaldehyde. J Phys Chem A 2017; 121:5459-5467. [PMID: 28671848 DOI: 10.1021/acs.jpca.7b05124] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Anion photoelectron imaging was used to measure the photodetachment spectra of molecular complexes formed between O2- and a range of atmospherically relevant polar molecules, including species with a carbonyl group (acetone, formaldehyde) and alcohols (ethanol, propenol, butenol). Experimental spectra are analyzed using a combination of Franck-Condon simulations and electronic structure calculations. Strong charge-dipole interactions and H-bonding stabilize the complex anions relative to the neutrals, resulting in a ca. 1 eV increase in electron binding energy relative to bare O2-, an effect more pronounced in complexes with H-bonding. In addition, broken degeneracy of the O2-local πg orbitals in the complexes results in the stabilization of the low-lying excited O2 (a 1Δg)·[polar VOC] state relative to the ground O2 (X 3Σg-)·[polar VOC] state when compared to bare O2. The spectra of the O2-·[polar VOC] complexes exhibit less pronounced laser photoelectron angular distribution (PADs). The spectrum of O2-·formaldehyde is unique in terms of both spectral profile and PAD. On the basis of these experimental results in addition to computational results, the complex anion cannot be described as a distinct O2- anion partnered with an innocent solvent molecule; the molecules are more strongly coupled through charge delocalization. Overall, the results underscore how the symmetry of the O2 πg orbitals is broken by different polar partners, which may have implications for atmospheric photochemistry and models of solar radiation absorption that include collision-induced absorption.
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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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10
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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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11
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Bogomolov AS, Kochubei SA, Baklanov AV. Oxygen-assisted excitation of methyl iodide as a test of double spin-flip transition in van der Waals complex CH3I-O2. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.08.059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Bogdanchikov GA, Baklanov AV. Calculations of the geometry and binding energy of the van der Waals complex of ethylene with oxygen C2H4–O2. J STRUCT CHEM+ 2015. [DOI: 10.1134/s0022476615050224] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Baklanov AV, Bogomolov AS, Pyryaeva AP, Bogdanchikov GA, Kochubei SA, Farooq Z, Parker DH. Singlet oxygen photogeneration from X–O2 van der Waals complexes: double spin-flip vs. charge-transfer mechanism. Phys Chem Chem Phys 2015; 17:28565-73. [DOI: 10.1039/c5cp03129j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The channel of singlet oxygen O2(1Δg) photogeneration from van der Waals complexes of oxygen X–O2 has been investigated to discriminate between two mechanisms based on charge-transfer or double spin-flip transitions.
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Affiliation(s)
- Alexey V. Baklanov
- Institute of Chemical Kinetics and Combustion
- Novosibirsk 630090
- Russia
- Novosibirsk State University
- Novosibirsk 630090
| | | | - Alexandra P. Pyryaeva
- Institute of Chemical Kinetics and Combustion
- Novosibirsk 630090
- Russia
- Novosibirsk State University
- Novosibirsk 630090
| | - Georgii A. Bogdanchikov
- Institute of Chemical Kinetics and Combustion
- Novosibirsk 630090
- Russia
- Novosibirsk State University
- Novosibirsk 630090
| | | | - Zahid Farooq
- Institute for Molecules and Materials
- Radboud University Nijmegen
- 6525 ED Nijmegen
- The Netherlands
| | - David H. Parker
- Institute for Molecules and Materials
- Radboud University Nijmegen
- 6525 ED Nijmegen
- The Netherlands
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14
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Oxygen-assisted enhancement of H atom UV-photogeneration from hydrocarbons in van der Waals complexes RH–O2. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2012.12.065] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Vidma KV, Frederix PWJM, Parker DH, Baklanov AV. Photodissociation of van der Waals clusters of isoprene with oxygen, C5H8-O2, in the wavelength range 213-277 nm. J Chem Phys 2012; 137:054305. [PMID: 22894346 DOI: 10.1063/1.4737856] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The speed and angular distribution of O atoms arising from the photofragmentation of C(5)H(8)-O(2), the isoprene-oxygen van der Waals complex, in the wavelength region of 213-277 nm has been studied with the use of a two-color dissociation-probe method and the velocity map imaging technique. Dramatic enhancement in the O atoms photo-generation cross section in comparison with the photodissociation of individual O(2) molecules has been observed. Velocity map images of these "enhanced" O atoms consisted of five channels, different in their kinetic energy, angular distribution, and wavelength dependence. Three channels are deduced to be due to the one-quantum excitation of the C(5)H(8)-O(2) complex into the perturbed Herzberg III state ((3)Δ(u)) of O(2). This excitation results in the prompt dissociation of the complex giving rise to products C(5)H(8)+O+O when the energy of exciting quantum is higher than the complex photodissociation threshold, which is found to be 41740 ± 200 cm(-1) (239.6±1.2 nm). This last threshold corresponds to the photodissociation giving rise to an unexcited isoprene molecule. The second channel, with threshold shifted to the blue by 1480 ± 280 cm(-1), corresponds to dissociation with formation of rovibrationally excited isoprene. A third channel was observed at wavelengths up to 243 nm with excitation below the upper photodissociation threshold. This channel is attributed to dissociation with the formation of a bound O atom C(5)H(8)-O(2) + hv → C(5)H(8)-O(2)((3)Δ(u)) → C(5)H(8)O + O and/or to dissociation of O(2) with borrowing of the lacking energy from incompletely cooled complex internal degrees of freedom C(5)H(8)*-O(2) + hv → C(5)H(8)*-O(2)((3)Δ(u)) → C(5)H(8) + O + O. The kinetic energy of the O atoms arising in two other observed channels corresponds to O atoms produced by photodissociation of molecular oxygen in the excited a (1)Δ(g) and b (1)Σ(g)(+) singlet states as the precursors. This indicates the formation of singlet oxygen O(2)(a (1)Δ(g)) and O(2)(b (1)Σ(g)(+)) after excitation of the C(5)H(8)-O(2) complex. Cooperative excitation of the complex with a simultaneous change of the spin of both partners (1)X-(3)O(2) + hν → (3)X-(1)O(2) → (3)X + (1)O(2) is suggested as a source of singlet oxygen O(2)(a (1)Δ(g)) and O(2)(b (1)Σ(g)(+)). This cooperative excitation is in agreement with little or no vibrational excitation of O(2)(a (1)Δ(g)), produced from the C(5)H(8)-O(2) complex as studied in the current paper as well as from the C(3)H(6)-O(2) and CH(3)I-O(2) complexes reported in our previous paper [Baklanov et al., J. Chem. Phys. 126, 124316 (2007)]. The formation of O(2)(a (1)Δ(g)) from C(5)H(8)-O(2) was observed at λ(pump) = 213-277 nm with the yield going down towards the long wavelength edge of this interval. This spectral profile is interpreted as the red-side wing of the band of a cooperative transition (1)X-(3)O(2) + hν → (3)X(T(2))-(1)O(2)(a (1)Δ(g)) in the C(5)H(8)-O(2) complex.
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Affiliation(s)
- Konstantin V Vidma
- Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 ED Nijmegen, The Netherlands
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Trushina AP, Goldort VG, Kochubei SA, Baklanov AV. Quantum Yield and Mechanism of Singlet Oxygen Generation via UV Photoexcitation of O2–O2 and N2–O2 Encounter Complexes. J Phys Chem A 2012; 116:6621-9. [DOI: 10.1021/jp301471e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Aleksandra P. Trushina
- Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090,
Russia
- Novosibirsk State University, Pirogova Str. 2, Novosibirsk
630090, Russia
| | - Veniamin G. Goldort
- Institute of Semiconductor Physics, Lavrentiev Ave. 13, Novosibirsk
630090, Russia
| | - Sergei A. Kochubei
- Institute of Semiconductor Physics, Lavrentiev Ave. 13, Novosibirsk
630090, Russia
| | - Alexey V. Baklanov
- Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090,
Russia
- Novosibirsk State University, Pirogova Str. 2, Novosibirsk
630090, Russia
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17
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Vidma KV, Bogdanchikov GA, Baklanov AV, Chestakov DA, Parker DH. Experimental measurement of the van der Waals binding energy of X–O2 clusters (X=Xe,CH3I,C3H6,C6H12). J Chem Phys 2010; 133:194306. [DOI: 10.1063/1.3503973] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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18
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Affiliation(s)
- Daniel P. Sanders
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95136
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19
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Costner EA, Long BK, Navar C, Jockusch S, Lei X, Zimmerman P, Campion A, Turro NJ, Willson CG. Fundamental Optical Properties of Linear and Cyclic Alkanes: VUV Absorbance and Index of Refraction. J Phys Chem A 2009; 113:9337-47. [DOI: 10.1021/jp903435c] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elizabeth A. Costner
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Brian K. Long
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Carlos Navar
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Steffen Jockusch
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Xuegong Lei
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Paul Zimmerman
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Alan Campion
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - Nicholas J. Turro
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
| | - C. Grant Willson
- Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, Department of Chemistry, The University of Texas at Austin, Austin, Texas, Department of Chemistry, Columbia Univeristy, New York, New York, and SEMATECH, Austin, Texas
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20
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Brownrigg JT, Kenny JE. Fluorescence Intensities and Lifetimes of Aromatic Hydrocarbons in Cyclohexane Solution: Evidence of Contact Charge-Transfer Interactions with Oxygen. J Phys Chem A 2009; 113:1049-59. [DOI: 10.1021/jp807495h] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- J. Thomas Brownrigg
- Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155
| | - Jonathan E. Kenny
- Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts 02155
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21
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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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22
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Baklanov AV, Bogdanchikov GA, Vidma KV, Chestakov DA, Parker DH. Cluster-enhanced X–O2 photochemistry (X=CH3I, C3H6, C6H12, and Xe). J Chem Phys 2007; 126:124316. [PMID: 17411132 DOI: 10.1063/1.2710268] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The effect of a local environment on the photodissociation of molecular oxygen is investigated in the van der Waals complex X-O(2) (X=CH(3)I, C(3)H(6), C(6)H(12), and Xe). A single laser operating at wavelengths around 226 nm is used for both photodissociation of the van der Waals complex and simultaneous detection of the O((3)P(J),J=2,1,0) atom photoproduct via (2+1) resonance enhanced multiphoton ionization. The kinetic energy distribution (KED) and angular anisotropy of the product O atom recoil in this dissociation are measured using the velocity map imaging technique configured for either full ("crush") or partial ("slice") detection of the three-dimensional O((3)P(J)) atom product Newton sphere. The measured KED and angular anisotropy reveal a distinct difference in the mechanism of O atom generation from an X-O(2) complex compared to a free O(2) molecule. The authors identify two one-photon excitation pathways, the relative importance of which depends on IPx, the ionization potential of the X partner. One pathway, observed for all complexes independent of IPx, involves a direct transition to the perturbed covalent state X-O(2)(A'(3)Delta(u)) with excitation localized on the O(2) subunit. The predominantly perpendicular character of this channel relative to the laser polarization detection, together with data on the structure of the complex, allows us to confirm that X partner induced admixing of an X(+)-O(2) (-) charge transfer (CT) state is the perturbing factor resulting in the well-known enhancement of photoabsorption within the Herzberg continuum of molecular oxygen. The second excitation pathway, observed for X-O(2) complexes with X=CH(3)I and C(3)H(6), involves direct excitation into the (3)(X(+)-O(2) (-)) CT state of the complex. The subsequent photodissociation of this CT state by the same laser pulse gives rise to the superoxide anion O(2) (-), which then photodissociates, providing fast (0.69 eV) O atoms with a parallel image pattern. Products from the photodissociation of singlet oxygen O(2)(b (1)Sigma(g) (+)) are also observed when the CH(3)I-O(2) complex was irradiated. Potential energy surfaces (PES) for the ground and relevant excited states of the X-O(2) complex have been constructed for CH(3)I-O(2) using the results of CASSCF calculations for the ground and CT states of the complex as well as literature data on PES of the subunits. These model potential energy surfaces allowed us to interpret all of the observed O((3)P(J)) atom production channels.
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Affiliation(s)
- Alexey V Baklanov
- Institute of Chemical Kinetics and Combustion, Institutskaja Street 3, Novosibirsk, Russia
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23
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Ashfold MNR, Nahler NH, Orr-Ewing AJ, Vieuxmaire OPJ, Toomes RL, Kitsopoulos TN, Garcia IA, Chestakov DA, Wu SM, Parker DH. Imaging the dynamics of gas phase reactions. Phys Chem Chem Phys 2006; 8:26-53. [PMID: 16482242 DOI: 10.1039/b509304j] [Citation(s) in RCA: 240] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ion imaging methods are making ever greater impact on studies of gas phase molecular reaction dynamics. This article traces the evolution of the technique, highlights some of the more important breakthroughs with regards to improving image resolution and in image processing and analysis methods, and then proceeds to illustrate some of the many applications to which the technique is now being applied--most notably in studies of molecular photodissociation and of bimolecular reaction dynamics.
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24
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Bowen MS, Becucci M, Continetti RE. Dissociative Photodetachment Dynamics of Solvated Iodine Cluster Anions. J Phys Chem A 2005; 109:11781-92. [PMID: 16366628 DOI: 10.1021/jp0547358] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Photoelectron-photofragment coincidence spectroscopy of I- (CO2), I- (NH3), I- (H2O), I- (C6H5NH2), and I- (C6H5OH) clusters was used to study the dissociative photodetachment (DPD) dynamics at 257 nm. Photodetachment from all five clusters was observed to yield bound neutral clusters as well as the DPD products of the iodine atom and the molecular solvent. Photoelectron images and kinetic energy spectra were recorded in coincidence with both the translational energy released between dissociating neutral products and stable neutral clusters. The variation of the photoelectron angular distributions in the clusters was measured, revealing significant perturbations relative to I- for I- (H2O) and I- (C6H5NH2). Product branching ratios for stable versus dissociative photodetachment and photodetachment to the I(2P(3/2)) and I(2P(1/2)) states are reported. The measurements reveal a dependence of the DPD dynamics on the final spin-orbit state of iodine in the cases of I- (C6H5NH2) and I- (CO2) and a threshold detachment process in I- (C6H5NH2).
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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, USA
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25
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Parsons BF, Chandler DW, Sklute EC, Li SL, Wade EA. Photodissociation Dynamics of ArNO Clusters. J Phys Chem A 2004. [DOI: 10.1021/jp047433z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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