1
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McGinnis KR, McGee CJ, Sommerfeld T, Jarrold CC. Anion Photoelectron Imaging Spectroscopy of C 6F 5X - (X = F, Cl, Br, I). J Phys Chem A 2024; 128:5646-5658. [PMID: 38980699 DOI: 10.1021/acs.jpca.4c03434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
The photoelectron (PE) spectra of C6F5X- (X = Cl, Br, I) and computational results on the anions and neutrals are presented and compared to previously reported results on C6F6- [McGee, C. J. J. Phys. Chem. A 2023, 127, 8556-8565.]. The spectra all exhibit broad, vibrationally unresolved detachment transitions, indicating that the equilibrium structures of the anions are significantly different from the neutrals. The PE spectrum of C6F5Cl- exhibits a parallel photoelectron angular distribution (PAD), similar to that of the previously reported C6F6- spectrum, while the PE spectra of C6F5Br- and C6F5I- have isotropic PADs, and also exhibit a prominent X- PE feature due to photodissociation of C6F5X- resulting in X- formation. Identification of the C6F5X- detachment transition origins, which is equivalent to the neutral electron affinity (EA), in all three cases is difficult, since the broadness of the detachment feature is accompanied by vanishingly small detachment cross section near the origin. Upper limits on the EAs were determined to be 1.70 eV for C6F5Cl, 2.10 eV for C6F5Br, and 2.00 eV for C6F5I, all significantly higher than the 0.76 eV upper limit determined for C6F6 with the same experiment. The broad detachment transitions are consistent with computational results, which predict very large differences between the neutral and anionic C-X (X = Cl, Br, I) bond lengths. Based on differences between the MBIS atom charges in the anions and neutrals, the excess charge in the anion is on the unique C atom and X, in contrast to the nonplanar C2v structured C6F6- anion, for which the charge is delocalized over the molecule. In C6F5Cl-, the C-Cl bond is predicted to be bent out of the plane, while both C6F5Br- and C6F5I- are predicted to be planar on average. The impact of the interruption of the symmetry in the hexafluorobenzene neutral and anion on the molecular and electronic structure of C6F5X/C6F5X- is considered, as well as the possible dissociative state leading to X- (X = Br, I) formation, and the nature of the C-X bond.
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Affiliation(s)
- Kristen Rose McGinnis
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Conor J McGee
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Thomas Sommerfeld
- Department of Chemistry and Physics, Southeast Louisiana University, SLU 10878, Hammond, Louisiana 70402, 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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Slimak S, Lietard A, Jordan KD, Verlet JRR. Effect of N Atom Substitution on Electronic Resonances: A 2D Photoelectron Spectroscopic and Computational Study of Anthracene, Acridine, and Phenazine Anions. J Phys Chem A 2024; 128:5321-5330. [PMID: 38935624 PMCID: PMC11247488 DOI: 10.1021/acs.jpca.4c02756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/15/2024] [Accepted: 06/17/2024] [Indexed: 06/29/2024]
Abstract
The accommodation of an excess electron by polycyclic aromatic hydrocarbons (PAHs) has important chemical and technological implications ranging from molecular electronics to charge balance in interstellar molecular clouds. Here, we use two-dimensional photoelectron spectroscopy and equation-of-motion coupled-cluster calculations of the radical anions of acridine (C13H9N-) and phenazine (C12H8N2-) and compare our results for these species to those for the anthracene anion (C14H10-). The calculations predict the observed resonances and additionally find low-energy two-particle-one-hole states, which are not immediately apparent in the spectra, and offer a slightly revised interpretation of the resonances in anthracene. The study of acridine and phenazine allows us to understand how N atom substitution affects electron accommodation. While the electron affinity associated with the ground state anion undergoes a sizable increase with the successive substitution of N atoms, the two lowest energy excited anion states are not affected significantly by the substitution. The net result is that there is an increase in the energy gap between the two lowest energy resonances and the bound ground electronic state of the radical anion from anthracene to acridine to phenazine. Based on an energy gap law for the rate of internal conversion, this increased gap makes ground state formation progressively less likely, as evidenced by the photoelectron spectra.
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Affiliation(s)
- Stephen Slimak
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Aude Lietard
- Department
of Chemistry, Durham University, Durham DH1 3LE, U.K.
| | - Kenneth D. Jordan
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Jan R. R. Verlet
- Department
of Chemistry, Durham University, Durham DH1 3LE, U.K.
- J.
Heyrovský Institute of Physical Chemistry, Czech Academy of
Sciences, Dolejškova
3, Prague 8 18223, Czech Republic
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3
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Ashworth EK, Ashworth SH, Bull JN. Spectroscopy and dynamics of isolated anions: Versatile instrumentation for photodetachment and photoelectron spectroscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:075103. [PMID: 38984887 DOI: 10.1063/5.0207759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 06/19/2024] [Indexed: 07/11/2024]
Abstract
Molecular anions are appealing targets for study because, compared with their neutral and cationic counterparts, they can be probed with conventional laboratory lasers without the need for multiphoton ionization schemes, and they provide spectroscopic details on the corresponding neutral molecules. Here, we describe a section of a modular instrument designed to perform high-throughput photoelectron and photodetachment spectroscopy of gas-phase anions, with future provision for time-resolved and isomer-selective spectroscopy. The instrument framework allows for the incorporation and adaptation of several ion sources, as demonstrated here with plasma (electric) discharge sources providing variable hard to soft ion generation conditions. The generated anions are separated according to their mass-to-charge ratio through time-of-flight mass spectrometry (m/zΔm/z = 500-600) and are focused into a set of perpendicular velocity-map imaging electrodes (ΔEE≈4%), where mass-selected anions are probed using laser light and the ejected electrons are velocity-map imaged. Instrument performance is demonstrated through the acquisition of photodetachment and photoelectron spectra for CH2CN-, showing sharp resonances in the vicinity of the detachment threshold assigned to rovibrational states of a dipole-bound anion and broader lifetime-limited spectral features at photon energies well above the threshold assigned to prompt autodetachment from a temporary anion resonance. Similar measurements could be performed on any molecular anions generated in the sources.
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Affiliation(s)
- Eleanor K Ashworth
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Stephen H Ashworth
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - James N Bull
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
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4
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Clarke CJ, Verlet JRR. Dynamics of Anions: From Bound to Unbound States and Everything In Between. Annu Rev Phys Chem 2024; 75:89-110. [PMID: 38277700 DOI: 10.1146/annurev-physchem-090722-125031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2024]
Abstract
Gas-phase anions present an ideal playground for the exploration of excited-state dynamics. They offer control in terms of the mass, extent of solvation, internal temperature, and conformation. The application of a range of ion sources has opened the field to a vast array of anionic systems whose dynamics are important in areas ranging from biology to star formation. Here, we review recent experimental developments in the field of anion photodynamics, demonstrating the detailed insight into photodynamical and electron-capture processes that can be uncovered. We consider the electronic and nuclear ultrafast dynamics of electronically bound excited states along entire reaction coordinates; electronically unbound states showing that photochemical concepts, such as chromophores and Kasha's rule, are transferable to electron-driven chemistry; and nonvalence states that straddle the interface between bound and unbound states. Finally, we consider likely developments that are sure to keep the field of anion dynamics buoyant and impactful.
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Affiliation(s)
- Connor J Clarke
- Department of Chemistry, Durham University, Durham, United Kingdom;
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham, United Kingdom;
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5
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Gibbard JA, Kellow CS, Verlet JRR. Photoelectron spectroscopy of the deprotonated tryptophan anion: the contribution of deprotomers to its photodetachment channels. Phys Chem Chem Phys 2024; 26:12053-12059. [PMID: 38578256 DOI: 10.1039/d4cp00309h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
Photoelectron spectroscopy and electronic structure calculations are used to investigate the electronic structure of the deprotonated anionic form of the aromatic amino acid tryptophan, and its chromophore, indole. The photoelectron spectra of tryptophan, recorded at different wavelengths across the UV, consist of two direct detachment channels and thermionic emission, whereas the hν = 4.66 eV spectrum of indole consists of two direct detachment features. Electronic structure calculations indicate that two deprotomers of tryptophan are present in the ion beam; deprotonation of the carboxylic acid group (Trp(I)-) or the N atom on the indole ring (Trp(II)-). Strong similarities are observed between the direct detachment channels in the photoelectron spectra of tryptophan and indole, which in conjunction with electronic structure calculations, indicate that electron loss from Trp(II)- dominates this portion of the spectra. However, there is some evidence that direct detachment of Trp(I)- is also observed. Thermionic emission is determined to predominantly arise from the decarboxylation of Trp(I)-, mediated by the ππ* excited state near λ = 300 nm, which results in an anionic fragment with a negative electron affinity that readily autodetaches.
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Affiliation(s)
- Jemma A Gibbard
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
| | | | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague 8, Czech Republic
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6
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McGinnis KR, McGee CJ, Jarrold CC. Isomer-Dependent Electron Affinities of Fluorophenyl Radicals, •C 6H 5-xF x (2 ≤ x ≤ 4). J Am Chem Soc 2024; 146:7063-7075. [PMID: 38440870 DOI: 10.1021/jacs.4c00556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
Di-, tri-, and tetrafluorophenyl radicals each have three regioisomers, several of which can form multiple distinct radical structures. We present the photoelectron spectra of the di-, tri-, and tetrafluorophenide regioisomer anions generated from their associated fluorobenzene precursors. By comparing the spectra to the results of density functional theory calculations, we determine that in cases where more than one possible radical isomer is possible for a given regioisomer (radicals formed from 1,2-difluorobenzene, 1,3-difluorobenzene, 1,2,3-trifluorobenzene, and 1,2,4-trifluorobenzene) the most stable anion corresponds to a less stable neutral, suggesting that the reactive C-center on these fluorine-substituted phenyl groups can be controlled by charge state. Full analyses of the spectra and computational results yield further insights into the differences between the electronic and molecular structures of the fluorophenyl radicals and their associated anions.
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Affiliation(s)
- Kristen Rose McGinnis
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Conor J McGee
- 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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7
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Gibbard JA, Reppel J, Verlet JRR. Photodissociation of permanganate (MnO 4-) produces the manganese dioxide anion (MnO 2-) in an excited triplet state. Phys Chem Chem Phys 2023. [PMID: 38018508 DOI: 10.1039/d3cp04576e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
Photoelectron imaging, electron action spectroscopy and electronic structure calculations are used to probe the structure and dynamics of MnO4-. Following excitation to the first bright absorption band of MnO4- (11T2), photodetachment, via ground state electron loss, and photodissociation, to produce MnO2-, are both observed to occur simultaneously. MnO2- is produced in an excited electronic state, identified as a triplet state, which indicates that the dissociation proceeds on singlet potential energy surfaces via spin conservation. Furthermore, electronic structure calculations indicate that both photodetachment and photodissociation are multiple photon processes that are mediated by the same 11T2 excited state. Taken together this data indicates that photodissociation of MnO4- occurs via a statistical dissociation on the MnO4- ground state at visible wavelengths.
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Affiliation(s)
- Jemma A Gibbard
- Department of Chemistry, Durham University, Durham DH1 3LE, UK.
| | - Jonathan Reppel
- Department of Chemistry, Durham University, Durham DH1 3LE, UK.
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, UK.
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8
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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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9
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Feng S, Li Z, Liu W, Zhang Q, Chen Y, Zhao D. Photoelectron Spectroscopy Confirms the Gas-Phase Stability of the C 3O 2- Anion. J Phys Chem Lett 2023; 14:8599-8603. [PMID: 37726868 DOI: 10.1021/acs.jpclett.3c02087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
The carbon suboxide anion with an asymmetric zigzag structure, C3O2-, which was recently characterized in a solid neon matrix, has not been observed in the gas phase. Here, we have experimentally generated C3O2- in a supersonic plasma jet expansion and studied it by negative ion photoelectron spectroscopy. A spectral analysis based on the calculated Franck-Condon factors, in combination with quantum chemical calculations, has for the first time yielded a determination of the electron affinity of the neutral carbon suboxide, EA = +0.48(8) eV. Molecular orbital (MO) analysis indicates that, upon linear-to-zigzag geometric change, additional σ-π MO mixing significantly reduces the energy of the singly occupied MO of C3O2- and thus stabilizes the negative ion in the gas phase. This work provides a benchmark understanding of the gas-phase stability of the C3O2- anion.
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Affiliation(s)
- Shaowen Feng
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Zhen Li
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Wenli Liu
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Qiang Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Yang Chen
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Dongfeng Zhao
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
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10
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Abstract
This Perspective attempts to shed light on developments in the theoretical and experimental study of molecular anions highlighting more recent workers in the field. The species I discuss include (i) valence-bound (singly and multiply charged) anions including atmospheric, catalytic, superhalogen, interfacial, and more; (ii) dipole- and correlation-bound anions including their role as doorways to other states and their appearance "in space", and (iii) metastable anions focusing on tools needed for their theoretical treatment. I also briefly discuss angular distributions of photodetached electrons and their growing utilization in experiments and theory. A recurring theme is the dependence of electron binding energies (EBEs) on the surrounding environment. Some anions that are nonexistent as isolated species evolve to be stable but with small EBEs when weakly solvated (e.g., as in a cluster or at an air-solvent interface). Others existing in isolation only as metastable species become stable when the underlying molecular framework contains one or more positively charged group (e.g., protonated side chains in a peptide) that generates a stabilizing Coulomb potential. On the other hand, a destabilizing Coulomb potential between/among negative sites in a multiply charged anion decreases the EBEs of each such site and generates a repulsive Coulomb barrier that can affect stability.
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Affiliation(s)
- Jack Simons
- Henry Eyring Center for Theoretical Chemistry, Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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11
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Minamikawa K, Nishizato T, Hashimoto H, Matsumoto K, Arakawa M, Horio T, Terasaki A. Probing Superatomic Orbitals of Sc-Doped and Undoped Silver Cluster Anions via Photoelectron Angular Anisotropy. J Phys Chem Lett 2023; 14:4011-4018. [PMID: 37083457 DOI: 10.1021/acs.jpclett.3c00538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Valence s electrons in alkali- or coinage-metal clusters are conceived to delocalize over the metal frameworks. The electrons occupy so-called superatomic orbitals (SAOs, i.e., 1S, 1P, 1D, 2S, 1F, ...), which provide an essential picture for understanding the size-dependent, unique properties of these metal clusters. While such electronic shells are unambiguously identified in their photoelectron spectra and supported by electronic structure calculations, characterization of SAOs in heteroatom-doped metal clusters has remained elusive as the doping significantly affects its energy levels and even alters the ordering of SAOs. Here, we present a photoelectron imaging study to explore SAOs formed in Sc-doped and undoped silver cluster anions, AgNSc- (N = 15, 16) and AgN- (N = 18, 19). Photoelectron angular distributions from their outermost SAOs are clearly visualized, whose characters are analyzed with the aid of density functional theory calculations. The present methodology enables us to explore not only the quantized energy levels but also the spatial distributions of SAOs formed in various metal cluster anions.
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Affiliation(s)
- K Minamikawa
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - T Nishizato
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - H Hashimoto
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - K Matsumoto
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - M Arakawa
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - T Horio
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - A Terasaki
- Department of Chemistry, Faculty of Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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12
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Ru B, Hart CA, Mabbs R, Gozem S, Krylov AI, Sanov A. Dipole effects in the photoelectron angular distributions of the sulfur monoxide anion. Phys Chem Chem Phys 2022; 24:23367-23381. [PMID: 36129043 DOI: 10.1039/d2cp03337b] [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
Photoelectron angular distributions (PADs) in SO- photodetachment using linearly polarized 355 nm (3.49 eV), 532 nm (2.33 eV), and 611 nm (2.03 eV) light were investigated via photoelectron imaging spectroscopy. The measurements at 532 and 611 nm access the X3Σ- and a1Δ electronic states of SO, whereas the measurements at 355 nm also access the b1Σ+ state. In aggregate, the photoelectron anisotropy parameter values follow the general trend with respect to electron kinetic energy (eKE) expected for π*-orbital photodetachment. The trend is similar to O2-, but the minimum of the SO- curve is shifted to smaller eKE. This shift is mainly attributed to the exit-channel interactions of the departing electron with the dipole moment of the neutral SO core, rather than the differing shapes of the SO- and O2- molecular orbitals. Of the several ab initio models considered, two approaches yield good agreement with the experiment: one representing the departing electron as a superposition of eigenfunctions of a point dipole-field Hamiltonian, and another describing the outgoing electron in terms of Coulomb waves originating from two separated charge centers, with a partial positive charge on the sulfur and an equal negative charge on the oxygen. These fundamentally related approaches support the conclusion that electron-dipole interactions in the exit channel of SO- photodetachment play an important role in shaping the PADs. While a similar conclusion was previously reached for photodetachment from σ orbitals of CN- (Hart, Lyle, Spellberg, Krylov, Mabbs, J. Phys. Chem. Lett., 2021, 12, 10086-10092), the present work includes the first extension of the dipole-field model to detachment from π* orbitals.
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Affiliation(s)
- Beverly Ru
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA.
| | - C Annie Hart
- Department of Chemistry, Washington University, Saint Louis, MO 63130, USA
| | - Richard Mabbs
- Department of Chemistry, Washington University, Saint Louis, MO 63130, USA
| | - Samer Gozem
- Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA
| | - Anna I Krylov
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA
| | - Andrei Sanov
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA.
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13
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Ranković M, Nag P, Anstöter CS, Mensa-Bonsu G, Kumar T P R, Verlet JRR, Fedor J. Resonances in nitrobenzene probed by the electron attachment to neutral and by the photodetachment from anion. J Chem Phys 2022; 157:064302. [PMID: 35963718 DOI: 10.1063/5.0101358] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We probe resonances (transient anions) in nitrobenzene with the focus on the electron emission from these. Experimentally, we populate resonances in two ways: either by the impact of free electrons on the neutral molecule or by the photoexcitation of the bound molecular anion. These two excitation means lead to transient anions in different initial geometries. In both cases, the anions decay by electron emission and we record the electron spectra. Several types of emission are recognized, differing by the way in which the resulting molecule is vibrationally excited. In the excitation of specific vibrational modes, distinctly different modes are visible in electron collision and photodetachment experiments. The unspecific vibrational excitation, which leads to the emission of thermal electrons following the internal vibrational redistribution, shows similar features in both experiments. A model for the thermal emission based on a detailed balance principle agrees with the experimental findings very well. Finally, a similar behavior in the two experiments is also observed for a third type of electron emission, the vibrational autodetachment, which yields electrons with constant final energies over a broad range of excitation energies. The entrance channels for the vibrational autodetachment are examined in detail, and they point to a new mechanism involving a reverse valence to non-valence internal conversion.
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Affiliation(s)
- Miloš Ranković
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - Pamir Nag
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Golda Mensa-Bonsu
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Ragesh Kumar T P
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Juraj Fedor
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czech Republic
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14
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Triptow J, Meijer G, Fielicke A, Dopfer O, Green M. Comparison of Conventional and Nonconventional Hydrogen Bond Donors in Au - Complexes. J Phys Chem A 2022; 126:3880-3892. [PMID: 35687835 PMCID: PMC9234979 DOI: 10.1021/acs.jpca.2c02725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although gold has become a well-known nonconventional hydrogen bond acceptor, interactions with nonconventional hydrogen bond donors have been largely overlooked. In order to provide a better understanding of these interactions, two conventional hydrogen bonding molecules (3-hydroxytetrahydrofuran and alaninol) and two nonconventional hydrogen bonding molecules (fenchone and menthone) were selected to form gas-phase complexes with Au-. The Au-[M] complexes were investigated using anion photoelectron spectroscopy and density functional theory. Au-[fenchone], Au-[menthone], Au-[3-hydroxyTHF], and Au-[alaninol] were found to have vertical detachment energies of 2.71 ± 0.05, 2.76 ± 0.05, 3.01 ± 0.03, and 3.02 ± 0.03 eV, respectively, which agree well with theory. The photoelectron spectra of the complexes resemble the spectrum of Au- but are blueshifted due to the electron transfer from Au- to M. With density functional theory, natural bond orbital analysis, and atoms-in-molecules analysis, we were able to extend our comparison of conventional and nonconventional hydrogen bonding to include geometric and electronic similarities. In Au-[3-hydroxyTHF] and Au-[alaninol], the hydrogen bonding comprised of Au-···HO as a strong, primary hydrogen bond, with secondary stabilization by weaker Au-···HN or Au-···HC hydrogen bonds. Interestingly, the Au-···HC bonds in Au-[fenchone] and Au-[menthone] can be characterized as hydrogen bonds, despite their classification as nonconventional hydrogen bond donors.
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Affiliation(s)
- Jenny Triptow
- Fritz-Haber-Institut der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.,Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Gerard Meijer
- Fritz-Haber-Institut der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - André Fielicke
- Fritz-Haber-Institut der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.,Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Otto Dopfer
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Mallory Green
- Fritz-Haber-Institut der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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15
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Gibbard JA, Verlet JRR. Photoelectron Imaging Study of the Diplatinum Iodide Dianions [Pt 2I 6] 2- and [Pt 2I 8] 2. J Phys Chem A 2022; 126:3495-3501. [PMID: 35621996 PMCID: PMC9189829 DOI: 10.1021/acs.jpca.2c02008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Photoelectron spectroscopy
has been used to study the electronic
structure, photodetachment, and photodissociation of the stable diplatinum
iodide dianions [Pt2I6]2– and
[Pt2I8]2–. Photoelectron spectra
over a range of photon energies show the characteristic absence of
low kinetic energy photoelectrons expected for dianions as a result
of the repulsive Coulomb barrier (RCB). Vertical detachment energies
of ∼1.6 and ∼1.9 eV and minimum RCBs of ∼1.2
and ∼1.3 eV are reported for [Pt2I6]2– and [Pt2I8]2–, respectively. Both of the diplatinum halides exhibit three direct
detachment channels with distinct anisotropies, analogous to the previously
reported spectra for PtI2– and PtI–, suggesting a platinum-centered molecular core that
dominates the photodetachment. Additionally, evidence for two-photon
photodissociation and subsequent photodetachment channels producing
I– are observed for both dianions. Finally, an unexplained
feature is observed at photon energies around 3 eV, whose origin is
considered. Our work highlights the complex electronic structure of
the heavy platinum-halide dianions that are characterized by a dense
manifold of electronic states.
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Affiliation(s)
- Jemma A Gibbard
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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16
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Anstöter CS, Verlet JRR. A Hückel Model for the Excited-State Dynamics of a Protein Chromophore Developed Using Photoelectron Imaging. Acc Chem Res 2022; 55:1205-1213. [PMID: 35172580 PMCID: PMC9084545 DOI: 10.1021/acs.accounts.1c00780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Chemistry can be described as the movement of nuclei within molecules and the concomitant instantaneous change in electronic structure. This idea underpins the central chemical concepts of potential energy surfaces and reaction coordinates. To experimentally capture such chemical change therefore requires methods that can probe both the nuclear and electronic structure simultaneously and on the time scale of atomic motion. In this Account, we show how time-resolved photoelectron imaging can do exactly this and how it can be used to build a detailed and intuitive understanding of the electronic structure and excited-state dynamics of chromophores. The chromophore of the photoactive yellow protein (PYP) is used as a case study. This chromophore contains a para-substituted phenolate anion, where the substituent, R, can be viewed as an acrolein derivative. It is shown that the measured photoelectron angular distribution can be directly related to the electronic structure of the para-substituted phenolate anion. By incrementally considering differing R groups, it is also shown that these photoelectron angular distributions are exquisitely sensitive to the conformational flexibility of R and that when R contains a π-system the excited states of the chromophore can be viewed as a linear combination of the π* molecular orbitals on the phenolate (πPh*) and the R substituent (πR*). Such Hückel treatment shows that the S1 state of the PYP chromophore has predominantly πR* character and that it is essentially the same as the chromophore of the green fluorescent protein (GFP). The S1 excited-state dynamics of the PYP chromophore probed by time-resolved photoelectron imaging clearly reveals both structural (nuclear) dynamics through the energy spectrum and electronic dynamics through the photoelectron angular distributions. Both motions can be accurately assigned using quantum chemical calculations, and these are consistent with the intuitive Hückel treatment presented. The photoactive protein chromophores considered here are examples of where a chemists' intuitive Hückel view for ground-state chemistry appears to be transferable to the prediction of photochemical excited-state reactivity. While elegant and insightful, such models have limitations, including nonadiabatic dynamics, which is present in a related PYP chromophore, where a fraction of the S1 state population forms a nonvalence (dipole-bound) state of the anion.
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Affiliation(s)
- Cate S. Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R. R. Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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17
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Gibbard JA, Verlet JRR. Photoelectron imaging of PtI 2 - and its PtI - photodissociation product. J Chem Phys 2022; 156:134303. [PMID: 35395905 DOI: 10.1063/5.0085610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The photoelectron imaging of PtI2 - is presented over photon energies ranging from hν = 3.2 to 4.5 eV. The electron affinity of PtI2 is found to be 3.4 ± 0.1 eV, and the photoelectron spectrum contains three distinct peaks corresponding to three low-lying neutral states. Using a simple d-block model and the measured photoelectron angular distributions, the three states are tentatively assigned. Photodissociation of PtI2 - is also observed, leading to the formation of I- and of PtI-. The latter allows us to determine the electron affinity of PtI to be 2.35 ± 0.10 eV. The spectrum of PtI- is similarly structured with three peaks which, again, can be tentatively assigned using a similar model that agrees with the photoelectron angular distributions.
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Affiliation(s)
- Jemma A Gibbard
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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18
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Photochemistry of the pyruvate anion produces CO 2, CO, CH 3-, CH 3, and a low energy electron. Nat Commun 2022; 13:937. [PMID: 35177613 PMCID: PMC8854594 DOI: 10.1038/s41467-022-28582-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 02/01/2022] [Indexed: 11/09/2022] Open
Abstract
The photochemistry of pyruvic acid has attracted much scientific interest because it is believed to play critical roles in atmospheric chemistry. However, under most atmospherically relevant conditions, pyruvic acid deprotonates to form its conjugate base, the photochemistry of which is essentially unknown. Here, we present a detailed study of the photochemistry of the isolated pyruvate anion and uncover that it is extremely rich. Using photoelectron imaging and computational chemistry, we show that photoexcitation by UVA light leads to the formation of CO2, CO, and CH3−. The observation of the unusual methide anion formation and its subsequent decomposition into methyl radical and a free electron may hold important consequences for atmospheric chemistry. From a mechanistic perspective, the initial decarboxylation of pyruvate necessarily differs from that in pyruvic acid, due to the missing proton in the anion. Pyruvic acid and its conjugate base, the pyruvate anion, are largely present in the atmosphere. Here the authors, using photoelectron imaging and quantum chemistry calculations, investigate the photochemistry of isolated pyruvate anions initiated by UVA radiation and report the formation of CO2, CO, and CH3− further decomposing into CH3 and a free electron.
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19
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Artemyev AN, Kutscher E, Demekhin PV. Photoelectron circular dichroism of a model chiral anion. J Chem Phys 2022; 156:031101. [DOI: 10.1063/5.0079723] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Anton N. Artemyev
- Institut für Physik und CINSaT, Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Eric Kutscher
- Institut für Physik und CINSaT, Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Philipp V. Demekhin
- Institut für Physik und CINSaT, Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
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20
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Anstöter CS, Curchod BFE, Verlet JRR. Photo-isomerization of the isolated photoactive yellow protein chromophore: what comes before the primary step? Phys Chem Chem Phys 2022; 24:1305-1309. [PMID: 34984423 DOI: 10.1039/d1cp05259d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Photoactive proteins typically rely on structural changes in a small chromophore to initiate a biological response. While these changes often involve isomerization as the "primary step", preceding this is an ultrafast relaxation of the molecular framework caused by the sudden change in electronic structure upon photoexcitation. Here, we capture this motion for an isolated model chromophore of the photoactive yellow protein using time-resolved photoelectron imaging. It occurs in <150 fs and is apparent from a spectral shift of ∼70 meV and a change in photoelectron anisotropy. Electronic structure calculations enable the quantitative assignment of the geometric and electronic structure changes to a planar intermediate from which the primary step can then proceed.
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Affiliation(s)
- Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, UK.
| | | | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, UK.
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21
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Dowek D, Decleva P. Trends in angle-resolved molecular photoelectron spectroscopy. Phys Chem Chem Phys 2022; 24:24614-24654. [DOI: 10.1039/d2cp02725a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In this perspective article, main trends of angle-resolved molecular photoelectron spectroscopy in the laboratory up to the molecular frame, in different regimes of light-matter interactions, are highlighted with emphasis on foundations and most recent applications.
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Affiliation(s)
- Danielle Dowek
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, 91405 Orsay, France
| | - Piero Decleva
- CNR IOM and Dipartimento DSCF, Università di Trieste, Trieste, Italy
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22
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Dauletyarov Y, Ru B, Sanov A. Anion of Oxalyl Chloride: Structure and Spectroscopy. J Phys Chem A 2021; 125:9865-9876. [PMID: 34732045 DOI: 10.1021/acs.jpca.1c07451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The structure and spectroscopy of the anion of oxalyl chloride are investigated using photoelectron imaging experiments and ab initio modeling. The photoelectron images, spectra, and angular distributions are obtained at 355 and 532 nm wavelengths. The 355 nm spectrum consists of a band assigned to a transition from the ground state of the anion to the ground state of the neutral. Its onset at ∼1.8 eV corresponds to the adiabatic electron affinity (EA) of oxalyl chloride, in agreement with the coupled-cluster calculations predicting an EA of 1.797 eV. The observed vertical detachment energy, 2.33(4) eV, is also in agreement with the theory predictions. The 532 nm spectrum additionally reveals a sharp onset near the photon-energy limit. This feature is ascribed to autodetachment via a low-energy anionic resonance. The results are discussed in the context of the substitution series, which includes glyoxal, methylglyoxal (single methyl substitution), biacetyl (double methyl substitution), and oxalyl chloride (double chlorine substitution). The EAs and anion detachment energies follow the trend: biacetyl < methylglyoxal < glyoxal ≪ oxalyl chloride. The electron-donating character of the methyl group has a destabilizing effect on the substituted anions, reducing the EA from glyoxal to methylglyoxal to biacetyl. In contrast, the strong electron-withdrawing (inductive) power of Cl lends additional stabilization to the oxalyl chloride anion, resulting in a large (∼1 eV) increase in its detachment energy compared to glyoxal.
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Affiliation(s)
- Yerbolat Dauletyarov
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Beverly Ru
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Andrei Sanov
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
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23
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Mason JL, Harb H, Abou Taka A, Huizenga CD, Corzo HH, Hratchian HP, Jarrold CC. New Photoelectron-Valence Electron Interactions Evident in the Photoelectron Spectrum of Gd 2O . J Phys Chem A 2021; 125:9892-9903. [PMID: 34730978 DOI: 10.1021/acs.jpca.1c07818] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Evidence of strong photoelectron-valence electron (PEVE) interactions has been observed in the anion photoelectron (PE) spectra of several lanthanide suboxide clusters, which are exceptionally complex from an electronic structure standpoint and are strongly correlated systems. The PE spectrum of Gd2O-, which should have relatively simple electronic structure because of its half-filled 4f subshell, exhibits numerous electronic transitions. The electron affinity determined from the spectrum is 0.26 eV. The intensities of transitions to excited states increase relative to the lower-energy states with lower photon energy, which is consistent with shakeup transitions driven by time-dependent electron-neutral interactions. A group of intense spectral features that lie between electron binding energies of 0.7 and 2.3 eV are assigned to transitions involving detachment of an electron from outer-valence σu and σg orbitals that have large Gd 6s contributions. The spectra show parallel transition manifolds in general, which is consistent with detachment from these orbitals. However, several distinct perpendicular transitions are observed adjacent to several of the vertical transitions. A possible explanation invoking interaction between the ejected electron and the high-spin neutral is proposed. Specifically, the angular momentum of electrons ejected from σu or σg orbitals, which is l = 1, can switch to l = 0, 2 with an associated change in the Ms of the remnant neutral, which is spin-orbit coupling between a free electron and the spin of a neutral.
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Affiliation(s)
- Jarrett L Mason
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Hassan Harb
- Department of Chemistry and Biochemistry, University of California, Merced, 5200 North Lake Road, Merced, California 95343, United States
| | - Ali Abou Taka
- Department of Chemistry and Biochemistry, University of California, Merced, 5200 North Lake Road, Merced, California 95343, United States
| | - Caleb D Huizenga
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Hector H Corzo
- Department of Chemistry and Biochemistry, University of California, Merced, 5200 North Lake Road, Merced, California 95343, United States
| | - Hrant P Hratchian
- Department of Chemistry and Biochemistry, University of California, Merced, 5200 North Lake Road, Merced, California 95343, United States
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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24
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Dobulis MA, McGee CJ, Sommerfeld T, Jarrold CC. Autodetachment over Broad Photon Energy Ranges in the Anion Photoelectron Spectra of [O 2- M] - ( M = Glyoxal, Methylglyoxal, or Biacetyl) Complex Anions. J Phys Chem A 2021; 125:9128-9142. [PMID: 34623818 DOI: 10.1021/acs.jpca.1c07163] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Complexes of anion-neutral pairs are prevalent in chemical and physical processes in the interstellar medium, the atmosphere, and biological systems, among others. However, bimolecular anionic species that cannot be described as simple ion-molecule complexes due to their competitive electron affinities have received less attention. In this study, the [O2-M]- (M = glyoxal, methylglyoxal, or biacetyl) anion photoelectron spectra obtained with several different photon energies are reported and interpreted in the context of ab initio calculations. The spectra do not resemble the photoelectron spectra of M- or O2- "solvated" by a neutral partner. Rather, all spectra are dominated by near-threshold autodetachment from what are likely transient dipole bound states of the cis conformers of the complex anions. Very low Franck-Condon overlap between the neutral M·O2 van der Waals clusters and the partial covalently bound complex anions results in low-intensity, broad direct detachment observed in the spectra. The [O2-glyoxal]- spectra measured with 2.88 and 3.495 eV photon energies additionally exhibit features at ∼0.5 eV electron kinetic energy, which is more difficult to explain, though there are numerous quasibound states of the anion that may be involved. Overall, these features point to the inadequacy of describing the complex anions as simple ion-molecule complexes.
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Affiliation(s)
- Marissa A Dobulis
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Conor J McGee
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Thomas Sommerfeld
- Department of Chemistry and Physics, Southeast Louisiana University, SLU 10878, Hammond, Louisiana 70402, United States
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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25
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Babin MC, DeWitt M, DeVine JA, McDonald DC, Ard SG, Shuman NS, Viggiano AA, Cheng L, Neumark DM. Electronic structure of NdO via slow photoelectron velocity-map imaging spectroscopy of NdO --. J Chem Phys 2021; 155:114305. [PMID: 34551540 DOI: 10.1063/5.0063307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Electronically excited NdO is a possible product of the chemistry associated with the release of Nd into the ionosphere, and emission from these states may contribute to the observations following such experiments. To better characterize the energetics and spectroscopy of NdO, we report a combined experimental and theoretical study using slow photoelectron velocity-map imaging spectroscopy of cryogenically cooled NdO- anions (cryo-SEVI) supplemented by wave function-based quantum-chemical calculations. Using cryo-SEVI, we measure the electron affinity of NdO to be 1.0091(7) eV and resolve numerous transitions to low-lying electronic and vibrational states of NdO that are assigned with the aid of the electronic structure calculations. Additionally, temperature-dependent data suggest contributions from the (2)4.5 state of NdO- residing 2350 cm-1 above the ground anion state. Photodetachment to higher-lying excited states of NdO is also reported, which may help to clarify observations from prior release experiments.
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Affiliation(s)
- Mark C Babin
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA
| | - Martin DeWitt
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA
| | - Jessalyn A DeVine
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA
| | - David C McDonald
- NRC Postdoc at Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, USA
| | - Shaun G Ard
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, USA
| | - Nicholas S Shuman
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, USA
| | - Albert A Viggiano
- Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, Albuquerque, New Mexico 87117, USA
| | - Lan Cheng
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA
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26
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Lietard A, Verlet JRR, Slimak S, Jordan KD. Temporary Anion Resonances of Pyrene: A 2D Photoelectron Imaging and Computational Study. J Phys Chem A 2021; 125:7004-7013. [PMID: 34369146 DOI: 10.1021/acs.jpca.1c05586] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The low-energy electron-scattering resonances of pyrene were characterized using experimental and computational methods. Experimentally, a two-dimensional photoelectron imaging of the pyrene anion was used to probe the dynamics of resonances over the first 4 eV of the continuum. Computationally, the energies and character of the anion states were determined using equation-of-motion coupled cluster calculations, while taking specific care to avoid the collapse onto discretized continuum levels, and an application of the pairing theorem. Our results are in good agreement with the predictions of electron-scattering calculations that include an offset and with the pyrene anion absorption spectrum in a glass matrix. Taken together, we offer an assignment of the first five electronic resonances of pyrene. Some of the population in the lowest-energy 2B1u resonance was observed to decay to the ground electronic state of the anion, while all other resonances decay by a direct autodetachment. The astronomical relevance of a ground-state electron capture proceeding via a low-energy resonance in pyrene is discussed.
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Affiliation(s)
- Aude Lietard
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Stephen Slimak
- Department of Chemistry, University of Pittsburgh, Pittsburgh 15260, Pennsylvania, United States
| | - Kenneth D Jordan
- Department of Chemistry, University of Pittsburgh, Pittsburgh 15260, Pennsylvania, United States
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27
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Krüger P, Weitzel K. Photoelektronen‐Zirkulardichroismus im Photodetachment von Aminosäuren‐Anionen. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Peter Krüger
- Fachbereich Chemie Philipps-Universität Marburg 35032 Marburg Deutschland
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28
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Krüger P, Weitzel K. Photoelectron Circular Dichroism in the Photodetachment of Amino Acid Anions. Angew Chem Int Ed Engl 2021; 60:17861-17865. [PMID: 34137142 PMCID: PMC8457165 DOI: 10.1002/anie.202107150] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Indexed: 01/31/2023]
Abstract
The chirality of chemical compounds is of undisputed importance in science and technology. In particular with respect to pharmacological application most molecules of interest cannot be accessed by the powerful techniques developed in recent years for gas phase analytes. Here, we demonstrate that the combination of electrospray ionization (ESI) with the detection of photoelectron circular dichroism (PECD) provides access to chirality information applicable to molecular materials with negligible vapor pressure, for example, amino acids. To this end, glutamic acid and 3,4-dihydroxyphenylalanine (DOPA) have been electrosprayed into the source of a chirality spectrometer, where photodetachment is enforced and the PECD is detected. The technique can be expected to be conceptually applicable to all chemical systems with chirality based on molecular properties.
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Affiliation(s)
- Peter Krüger
- Fachbereich ChemiePhilipps-Universität Marburg35032MarburgGermany
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29
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Huizenga C, Hratchian HP, Jarrold CC. Lanthanide Oxides: From Diatomics to High-Spin, Strongly Correlated Homo- and Heterometallic Clusters. J Phys Chem A 2021; 125:6315-6331. [PMID: 34265204 DOI: 10.1021/acs.jpca.1c04253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Small lanthanide (Ln) oxide clusters present both experimental and theoretical challenges because of their partially filled, core-like 4f n orbitals, a feature that results in a plethora of close-lying and fundamentally similar electronic states. These clusters provide a bottom-up approach toward understanding the electronic structure of defective or doped bulk material but also can offer a challenge to the theorists to find a method robust enough to capture electronic structure patterns that emerge from within the 4f n (0 < n < 14) series. In this Feature Article, we explore the electronic structures of small lanthanide oxide clusters that deviate from bulk stoichiometry using anion photoelectron spectroscopy and supporting density functional theory calculations. We will describe the evolution of electronic structure with oxidation and how LnxOy- cluster reactivities can be correlated with specific Ln-local orbital occupancies. These strongly correlated systems offer additional insights into how interactions between electrons and electronically complex neutrals can lead to detachment transitions that lie outside of the sudden one-electron detachment approximation generally assumed in anion photoelectron spectroscopy. With a better understanding of how we can control nominally forbidden transitions to sample an array of spin states, we suggest that more in-depth studies on the magnetic states of these systems can be explored. Extending these studies to other Ln-based materials with hidden magnetic phases, along with sequentially ligated single molecule magnets, could advance current understanding of these systems.
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Affiliation(s)
- Caleb Huizenga
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Hrant P Hratchian
- Department of Chemistry and Chemical Biology, University of California, Merced, 5200 North Lake Road, Merced, California 95343, United States
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
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30
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Lu Y, Tang R, Ning C. Observation of an Excited Dipole-Bound State in a Diatomic Anion. J Phys Chem Lett 2021; 12:5897-5902. [PMID: 34151577 DOI: 10.1021/acs.jpclett.1c01726] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We report the observation of σ-type and π-type excited dipole-bound states (DBSs) in cryogenically cooled potassium iodide (KI) anions for the first time. Two DBSs were observed 39.7(10) meV and 5.0(12) meV below the photodetachment threshold via the resonant two-photon detachment. The different photoelectron angular distributions and binding energies suggest that the two DBSs are of different types. The existence of one σ-type and one π-type DBS in the KI anion was also supported by the high-level ab initio theoretical calculations. The excellent agreement between experimental and theoretical results confirms the prediction that a dipolar molecule with a large enough dipole moment can have an excited DBS.
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Affiliation(s)
- Yuzhu Lu
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 10084, China
| | - Rulin Tang
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 10084, China
| | - Chuangang Ning
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 10084, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
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31
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Piechaczek A, Bartels C, Hock C, Rost JM, von Issendorff B. Decoherence-Induced Universality in Simple Metal Cluster Photoelectron Angular Distributions. PHYSICAL REVIEW LETTERS 2021; 126:233201. [PMID: 34170164 DOI: 10.1103/physrevlett.126.233201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/26/2021] [Accepted: 05/05/2021] [Indexed: 06/13/2023]
Abstract
Measured angular distributions of photoelectrons from size-selected copper and sodium cluster anions are demonstrated to exhibit a universal behavior independent of the initial electron state, cluster size, or material, which can be traced back to momentum conservation upon photoemission. Quantum simulations reproduce the universality under the assumption that multielectron dynamics localizes the emission on the cluster surface and renders the cluster opaque to photoelectrons, thereby quenching interference effects that would otherwise obscure this almost classical behavior.
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Affiliation(s)
- Adam Piechaczek
- Institute of Physics, University of Freiburg, Hermann-Herder-Straße 3, 79104 Freiburg, Germany
| | - Christof Bartels
- Institute of Physics, University of Freiburg, Hermann-Herder-Straße 3, 79104 Freiburg, Germany
| | - Christian Hock
- Institute of Physics, University of Freiburg, Hermann-Herder-Straße 3, 79104 Freiburg, Germany
| | - Jan-Michael Rost
- Max-Planck-Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany
| | - Bernd von Issendorff
- Institute of Physics, University of Freiburg, Hermann-Herder-Straße 3, 79104 Freiburg, Germany
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32
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Anstöter CS, Verlet JRR. Modeling the Photoelectron Angular Distributions of Molecular Anions: Roles of the Basis Set, Orbital Choice, and Geometry. J Phys Chem A 2021; 125:4888-4895. [PMID: 34042462 DOI: 10.1021/acs.jpca.1c03379] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A study investigating the effect of the basis set, orbital choice, and geometry on the modeling of photoelectron angular distributions (PADs) of molecular anions is presented. Experimental and modeled PADs for a number of molecular anions, including both closed- and open-shell systems, are considered. Guidelines are suggested for chemists who wish to design calculations to capture the correct chemical physics of the anisotropy of photodetachment, while balancing the computational cost associated with larger molecular anions.
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Affiliation(s)
- Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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33
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Gozem S, Krylov AI. The
ezSpectra
suite: An easy‐to‐use toolkit for spectroscopy modeling. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2021. [DOI: 10.1002/wcms.1546] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Samer Gozem
- Department of Chemistry Georgia State University Atlanta Georgia USA
| | - Anna I. Krylov
- Department of Chemistry University of Southern California Los Angeles California USA
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34
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Mason JL, Folluo CN, Jarrold CC. More than little fragments of matter: Electronic and molecular structures of clusters. J Chem Phys 2021; 154:200901. [DOI: 10.1063/5.0054222] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jarrett L. Mason
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA
| | - Carley N. Folluo
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA
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35
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Yuan DF, Zhang YR, Qian CH, Liu Y, Wang LS. Probing the Dipole-Bound State in the 9-Phenanthrolate Anion by Photodetachment Spectroscopy, Resonant Two-Photon Photoelectron Imaging, and Resonant Photoelectron Spectroscopy. J Phys Chem A 2021; 125:2967-2976. [DOI: 10.1021/acs.jpca.1c01563] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Dao-Fu Yuan
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Yue-Rou Zhang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Chen-Hui Qian
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Yuan Liu
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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36
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Anstöter CS, Verlet JRR. Photoelectron imaging of the SO 3 anion: vibrational resolution in photoelectron angular distributions*. Mol Phys 2021. [DOI: 10.1080/00268976.2020.1821921] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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37
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Abstract
Electron capture by the σ* LUMO of isoxazole triggers the dissociation of the O-N bond and the opening of the ring. Photodetachment of the resulting anion accesses a neutral structure, in which the O· and ·N bond fragments interact through the intact remainder of the molecular ring and via a 3 Å gap created by the bond dissociation. These through-bond and through-space interactions result in a dense manifold of diradical states, including (in the order of increasing energy) a triplet, an open-shell singlet, a closed-shell singlet, and another triplet state. We report photoelectron spectra that reflect partially resolved signatures of these states. Remarkably, the structure of the isoxazole diradical manifold is qualitatively different from that of the analogous system in oxazole. The distinct properties of the two manifolds are explained by using a coupled-fragments molecular-orbital model. Consistent with the past conclusions [Culberson et al. Phys. Chem. Chem. Phys. 2014, 16, 3964-3972], the lingering through-space interactions between the O· and ·C bond fragments in ring-open oxazole are responsible for the relative stabilization of the closed-shell singlet state, which correlates with the ground-state cyclic structure. In contrast, the placement of the N atom in the terminal position within the ring-open structure of isoxazole is the key factor leading to the near degeneracy of the π and σ* orbitals, favoring a triplet-state configuration.
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Affiliation(s)
- Adam A Wallace
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, United States
| | - Yerbolat Dauletyarov
- 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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38
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Abou Taka A, Babin MC, Sheng X, DeVine JA, Neumark DM, Hratchian HP. Unveiling the coexistence of cis- and trans-isomers in the hydrolysis of ZrO2: A coupled DFT and high-resolution photoelectron spectroscopy study. J Chem Phys 2020; 153:244308. [DOI: 10.1063/5.0037636] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Affiliation(s)
- Ali Abou Taka
- Department of Chemistry & Chemical Biology, Center for Chemical Computation and Theory, University of California, Merced, California 95343, USA
| | - Mark C. Babin
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Xianghai Sheng
- Department of Chemistry & Chemical Biology, Center for Chemical Computation and Theory, University of California, Merced, California 95343, USA
| | - Jessalyn A. DeVine
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Daniel M. Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Hrant P. Hratchian
- Department of Chemistry & Chemical Biology, Center for Chemical Computation and Theory, University of California, Merced, California 95343, USA
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39
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Blackstone CC, Wallace AA, Sanov A. Photoelectron angular distributions in photodetachment from polarised d-like states: the case of HO2−. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1831636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
| | - Adam A. Wallace
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ, USA
| | - Andrei Sanov
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, AZ, USA
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40
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Simons J. Ejecting Electrons from Molecular Anions via Shine, Shake/Rattle, and Roll. J Phys Chem A 2020; 124:8778-8797. [DOI: 10.1021/acs.jpca.0c08016] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jack Simons
- Henry Eyring Center for Theoretical Chemistry, Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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41
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Babin MC, DeWitt M, Weichman ML, DeVine JA, Neumark DM. High-resolution anion photoelectron spectroscopy of cryogenically cooled 4-atom silicon carbides. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1817596] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Mark C. Babin
- Department of Chemistry, University of California, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Martin DeWitt
- Department of Chemistry, University of California, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Marissa L. Weichman
- Department of Chemistry, University of California, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jessalyn A. DeVine
- Department of Chemistry, University of California, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Daniel M. Neumark
- Department of Chemistry, University of California, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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42
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Affiliation(s)
- Anna I. Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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43
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Wallace AA, Dauletyarov Y, Sanov A. Deprotonation of Isoxazole: A Photoelectron Imaging Study. J Phys Chem A 2020; 124:7768-7775. [DOI: 10.1021/acs.jpca.0c06838] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Adam A. Wallace
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, United States
| | - Yerbolat Dauletyarov
- 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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44
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Anstöter CS, Verlet JRR. Gas-Phase Synthesis and Characterization of the Methyl-2,2-dicyanoacetate Anion Using Photoelectron Imaging and Dipole-Bound State Autodetachment. J Phys Chem Lett 2020; 11:6456-6462. [PMID: 32687376 DOI: 10.1021/acs.jpclett.0c02036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The methyl-2,2-dicyanoacetate anion is synthesized in an electrospray ionization source through a gas-phase reaction involving tetracyanoethylene and methanol. Photoelectron imaging is used to determine the isomeric form of the product. The photoelectron spectra and angular distributions are consistent with only a single isomer. Additionally, mode-specific vibrational autodetachment is observed. This can be correlated with the emission from a photoexcited dipole-bound state by considering the IR spectrum of the neutral molecule, adding further confirmation of the isomeric form and providing a binding energy of the dipole-bound state. Our experiments show how conventional photoelectron imaging can be used to determine detailed information about gas-phase reaction products.
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Affiliation(s)
- Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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45
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Wang YT, Ning CG, Liu HT, Wang LS. High-Resolution Photoelectron Imaging and Photodetachment Spectroscopy of Cryogenically Cooled IO –. J Phys Chem A 2020; 124:5720-5726. [DOI: 10.1021/acs.jpca.0c04080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yong-Tian Wang
- Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chuan-Gang Ning
- Department of Physics, State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, P. R. China
| | - Hong-Tao Liu
- Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, P. R. China
| | - Lai-Sheng Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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46
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Anstöter CS, Curchod BFE, Verlet JRR. Geometric and electronic structure probed along the isomerisation coordinate of a photoactive yellow protein chromophore. Nat Commun 2020; 11:2827. [PMID: 32499507 PMCID: PMC7272410 DOI: 10.1038/s41467-020-16667-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/15/2020] [Indexed: 01/29/2023] Open
Abstract
Understanding the connection between the motion of the nuclei in a molecule and the rearrangement of its electrons lies at the heart of chemistry. While many experimental methods have been developed to probe either the electronic or the nuclear structure on the timescale of atomic motion, very few have been able to capture both these changes in concert. Here, we use time-resolved photoelectron imaging to probe the isomerisation coordinate on the excited state of an isolated model chromophore anion of the photoactive yellow protein. By probing both the electronic structure changes as well as nuclear dynamics, we are able to uniquely measure isomerisation about a specific bond. Our results demonstrate that the photoelectron signal dispersed in time, energy and angle combined with calculations can track the evolution of both electronic and geometric structure along the adiabatic state, which in turn defines that chemical transformation. Resolving concerted nuclear and electronic motion in real-time is a primary goal in chemistry. The authors monitor nuclear and valence electronic dynamics in the excited state single-bond isomerisation of a chromophore of photoactive yellow protein, using time-resolved photoelectron imaging and electronic structure calculations.
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Affiliation(s)
- Cate S Anstöter
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK
| | | | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
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47
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Verlet JRR, Anstöter CS, Bull JN, Rogers JP. Role of Nonvalence States in the Ultrafast Dynamics of Isolated Anions. J Phys Chem A 2020; 124:3507-3519. [PMID: 32233436 PMCID: PMC7212518 DOI: 10.1021/acs.jpca.0c01260] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Nonvalence states
of neutral molecules (Rydberg states) play important
roles in nonadiabatic dynamics of excited states. In anions, such
nonadiabatic transitions between nonvalence and valence states have
been much less explored even though they are believed to play important
roles in electron capture and excited state dynamics of anions. The
aim of this Feature Article is to provide an overview of recent experimental
observations, based on time-resolved photoelectron imaging, of valence
to nonvalence and nonvalence to valence transitions in anions and
to demonstrate that such dynamics may be commonplace in the excited
state dynamics of molecular anions and cluster anions.
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Affiliation(s)
- Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - James N Bull
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Joshua P Rogers
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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48
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Lu Y, Zhao J, Tang R, Fu X, Ning C. Measurement of electron affinity of iridium atom and photoelectron angular distributions of iridium anion. J Chem Phys 2020; 152:034302. [DOI: 10.1063/1.5134535] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yuzhu Lu
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
| | - Jing Zhao
- Security Printing Institute of People’s Bank of China, Beijing 100070, China
| | - Rulin Tang
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
| | - Xiaoxi Fu
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
| | - Chuangang Ning
- Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
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49
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Babin MC, DeVine JA, DeWitt M, Stanton JF, Neumark DM. High-Resolution Photoelectron Spectroscopy of Cryogenically Cooled NO 3̅. J Phys Chem Lett 2020; 11:395-400. [PMID: 31765169 DOI: 10.1021/acs.jpclett.9b03055] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
High-resolution anion photoelectron spectra of cryogenically cooled NO3̅ anions obtained using slow photoelectron velocity-map imaging are presented and provide new insight into the vibronic structure of the corresponding neutral radical. A combination of improved spectral resolution, measurement of energy-dependent intensity effects, temperature control, and comparison to theory allows for full assignment of the vibronic features observed in this spectrum. We obtain a refined electron affinity of 3.9289(14) eV for NO3. Further, the appearance of Franck-Condon forbidden transitions from vibrationally cold anions to neutral states with excitation along the NO3 ν4 mode confirms that these features arise from vibronic coupling with the B̃2E' excited state of NO3 and are not hot bands, as has been suggested. Together, the suite of experimental and simulated results provides clear evidence that the ν3 fundamental of NO3 resides near 1050 cm-1, addressing a long-standing controversy surrounding this vibrational assignment.
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Affiliation(s)
- Mark C Babin
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - Jessalyn A DeVine
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - Martin DeWitt
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
| | - John F Stanton
- Quantum Theory Project, Department of Chemistry and Physics , University of Florida , Gainesville , Florida 32611 , United States
| | - Daniel M Neumark
- Department of Chemistry , University of California , Berkeley , California 94720 , United States
- Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
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50
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Laws BA, Cavanagh SJ, Lewis BR, Gibson ST. Wigner Near-Threshold Effects in the Photoelectron Angular Distribution of NO2–. J Phys Chem A 2019; 123:10418-10425. [DOI: 10.1021/acs.jpca.9b09073] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- B. A. Laws
- Research School of Physics and Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - S. J. Cavanagh
- Research School of Physics and Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - B. R. Lewis
- Research School of Physics and Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - S. T. Gibson
- Research School of Physics and Engineering, The Australian National University, Canberra, ACT 2601, Australia
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