1
|
Remmerswaal WA, de Jong T, van de Vrande KNA, Louwersheimer R, Verwaal T, Filippov DV, Codée JDC, Hansen T. Backside versus Frontside S N2 Reactions of Alkyl Triflates and Alcohols. Chemistry 2024; 30:e202400590. [PMID: 38385647 DOI: 10.1002/chem.202400590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 02/23/2024]
Abstract
Nucleophilic substitution reactions are elementary reactions in organic chemistry that are used in many synthetic routes. By quantum chemical methods, we have investigated the intrinsic competition between the backside SN2 (SN2-b) and frontside SN2 (SN2-f) pathways using a set of simple alkyl triflates as the electrophile in combination with a systematic series of phenols and partially fluorinated ethanol nucleophiles. It is revealed how and why the well-established mechanistic preference for the SN2-b pathway slowly erodes and can even be overruled by the unusual SN2-f substitution mechanism going from strong to weak alcohol nucleophiles. Activation strain analyses disclose that the SN2-b pathway is favored for strong alcohol nucleophiles because of the well-known intrinsically more efficient approach to the electrophile resulting in a more stabilizing nucleophile-electrophile interaction. In contrast, the preference of weaker alcohol nucleophiles shifts to the SN2-f pathway, benefiting from a stabilizing hydrogen bond interaction between the incoming alcohol and the leaving group. This hydrogen bond interaction is strengthened by the increased acidity of the weaker alcohol nucleophiles, thereby steering the mechanistic preference toward the frontside SN2 pathway.
Collapse
Affiliation(s)
- Wouter A Remmerswaal
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Tjeerd de Jong
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Koen N A van de Vrande
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Rick Louwersheimer
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Thomas Verwaal
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Dmitri V Filippov
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Jeroen D C Codée
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
| | - Thomas Hansen
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC, Leiden, The, Netherlands
- Department of Chemistry and Pharmaceutical Sciences, AIMMS, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ, Amsterdam, The, Netherlands
| |
Collapse
|
2
|
Wang X, Hasan M, Fan L, Wang Y, Li H, Slaughter DS, Centurion M. Mass-selected ion-molecule cluster beam apparatus for ultrafast photofragmentation studies. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:095111. [PMID: 37724931 DOI: 10.1063/5.0148194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/31/2023] [Indexed: 09/21/2023]
Abstract
We describe an apparatus for investigating the excited-state dissociation dynamics of mass-selected ion-molecule clusters by mass-resolving and detecting photofragment-ions and neutrals, in coincidence, using an ultrafast laser operating at high repetition rates. The apparatus comprises a source that generates ion-molecule clusters, a time-of-flight spectrometer, and a mass filter that selects the desired anions, and a linear-plus-quadratic reflectron mass spectrometer that discriminates the fragment anions after the femtosecond laser excites the clusters. The fragment neutrals and anions are then captured by two channeltron detectors. The apparatus performance is tested by measuring the photofragments: I-, CF3I-, and neutrals from photoexcitation of the ion-molecule cluster CF3I·I- using femtosecond UV laser pulses with a wavelength of 266 nm. The experimental results are compared with our ground state and excited state electronic structure calculations as well as the existing results and calculations, with particular attention to the generation mechanism of the anion fragments and dissociation channels of the ion-molecule cluster CF3I·I- in the charge-transfer excited state.
Collapse
Affiliation(s)
- Xiaojun Wang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Mahmudul Hasan
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Lin Fan
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Yibo Wang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Hui Li
- Department of Chemistry, Nebraska Center for Materials and Nanoscience, and Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Daniel S Slaughter
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, California 94720, USA
| | - Martin Centurion
- Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| |
Collapse
|
3
|
Robinson HT, Haakansson CT, Corkish TR, Watson PD, McKinley AJ, Wild DA. Hydrogen Bonding versus Halogen Bonding: Spectroscopic Investigation of Gas-Phase Complexes Involving Bromide and Chloromethanes. Chemphyschem 2022; 24:e202200733. [PMID: 36504309 DOI: 10.1002/cphc.202200733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/12/2022] [Accepted: 12/12/2022] [Indexed: 12/14/2022]
Abstract
Hydrogen bonding and halogen bonding are important non-covalent interactions that are known to occur in large molecular systems, such as in proteins and crystal structures. Although these interactions are important on a large scale, studying hydrogen and halogen bonding in small, gas-phase chemical species allows for the binding strengths to be determined and compared at a fundamental level. In this study, anion photoelectron spectra are presented for the gas-phase complexes involving bromide and the four chloromethanes, CH3 Cl, CH2 Cl2 , CHCl3 , and CCl4 . The stabilisation energy and electron binding energy associated with each complex are determined experimentally, and the spectra are rationalised by high-level CCSD(T) calculations to determine the non-covalent interactions binding the complexes. These calculations involve nucleophilic bromide and electrophilic bromine interactions with chloromethanes, where the binding motifs, dissociation energies and vertical detachment energies are compared in terms of hydrogen bonding and halogen bonding.
Collapse
Affiliation(s)
- Hayden T Robinson
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, 6009
| | - Christian T Haakansson
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, 6009
| | - Timothy R Corkish
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, 6009
| | - Peter D Watson
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, 6009.,Department of Chemistry, University of Oxford, South Parks Road, Oxford, United Kingdom, OX1 3QZ
| | - Allan J McKinley
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, 6009
| | - Duncan A Wild
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia, 6009.,School of Science, Edith Cowan University, Joondalup, Western Australia, 6027
| |
Collapse
|
4
|
Stabilizing Halogen-Bonded Complex between Metallic Anion and Iodide. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27228069. [PMID: 36432170 PMCID: PMC9692347 DOI: 10.3390/molecules27228069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 11/22/2022]
Abstract
Halogen bonds (XBs) between metal anions and halides have seldom been reported because metal anions are reactive for XB donors. The pyramidal-shaped Mn(CO)5- anion is a candidate metallic XB acceptor with a ligand-protected metal core that maintains the negative charge and an open site to accept XB donors. Herein, Mn(CO)5- is prepared by electrospray ionization, and its reaction with CH3I in gas phase is studied using mass spectrometry and density functional theory (DFT) calculation. The product observed experimentally at m/z = 337 is assigned as [IMn(CO)4(OCCH3)]-, which is formed by successive nucleophilic substitution and reductive elimination, instead of the halogen-bonded complex (XC) CH3-I···Mn(CO)5-, because the I···Mn interaction is weak within XC and it could be a transient species. Inspiringly, DFT calculations predict that replacing CH3I with CF3I can strengthen the halogen bonding within the XC due to the electro-withdrawing ability of F. More importantly, in so doing, the nucleophilic substitution barrier can be raised significantly, ~30 kcal/mol, thus leaving the system trapping within the XC region. In brief, the combination of a passivating metal core and the introduction of an electro-withdrawing group to the halide can enable strong halogen bonding between metallic anion and iodide.
Collapse
|
5
|
Robinson HT, Corkish TR, Haakansson CT, Watson PD, McKinley AJ, Wild DA. Spectroscopic Study of the Br - +CH 3 I→I - +CH 3 Br S N 2 Reaction. Chemphyschem 2022; 23:e202200278. [PMID: 35708114 PMCID: PMC9804238 DOI: 10.1002/cphc.202200278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 06/06/2022] [Indexed: 01/05/2023]
Abstract
Mass spectrometry and anion photoelectron spectroscopy have been used to study the gas-phase <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msub><mml:mi>S</mml:mi> <mml:mi>N</mml:mi></mml:msub> <mml:mn>2</mml:mn></mml:mrow> <mml:annotation>${{{\rm S}}_{{\rm N}}2}$</mml:annotation> </mml:semantics> </mml:math> reaction involving <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:msup><mml:mrow><mml:mi>B</mml:mi> <mml:mi>r</mml:mi></mml:mrow> <mml:mo>-</mml:mo></mml:msup> <mml:annotation>${{{\rm B}{\rm r}}^{-}}$</mml:annotation> </mml:semantics> </mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow> <mml:msub><mml:mrow><mml:mi>C</mml:mi> <mml:mi>H</mml:mi></mml:mrow> <mml:mn>3</mml:mn></mml:msub> <mml:mi>I</mml:mi></mml:mrow> <mml:annotation>${{{\rm C}{\rm H}}_{3}{\rm I}}$</mml:annotation> </mml:semantics> </mml:math> . The anion photoelectron spectra associated with the reaction intermediates of this <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msub><mml:mi>S</mml:mi> <mml:mi>N</mml:mi></mml:msub> <mml:mn>2</mml:mn></mml:mrow> <mml:annotation>${{{\rm S}}_{{\rm N}}2}$</mml:annotation> </mml:semantics> </mml:math> reaction are presented. High-level CCSD(T) calculations have been utilised to investigate the reaction intermediates that may form as a result of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:msub><mml:mi>S</mml:mi> <mml:mi>N</mml:mi></mml:msub> <mml:mn>2</mml:mn></mml:mrow> <mml:annotation>${{{\rm S}}_{{\rm N}}2}$</mml:annotation> </mml:semantics> </mml:math> reaction along various different reaction pathways, including back-side attack and front-side attack. In addition, simulated vertical detachment energies of each reaction intermediate have been calculated to rationalise the photoelectron spectra.
Collapse
Affiliation(s)
- Hayden T. Robinson
- School of Molecular SciencesThe University of Western AustraliaCrawleyWestern Australia6009
| | - Timothy R. Corkish
- School of Molecular SciencesThe University of Western AustraliaCrawleyWestern Australia6009
| | | | - Peter D. Watson
- School of Molecular SciencesThe University of Western AustraliaCrawleyWestern Australia6009,Department of ChemistryUniversity of OxfordSouth Parks RoadOxfordUnited KingdomOX1 3QZ
| | - Allan J. McKinley
- School of Molecular SciencesThe University of Western AustraliaCrawleyWestern Australia6009
| | - Duncan A. Wild
- School of Molecular SciencesThe University of Western AustraliaCrawleyWestern Australia6009,School of ScienceEdith Cowan UniversityJoondalupWestern Australia6027
| |
Collapse
|
6
|
Zhao S, Fu G, Zhen W, Yang L, Sun J, Zhang J. Reaction mechanism conversion induced by the contest of nucleophile and leaving group. Phys Chem Chem Phys 2022; 24:24146-24154. [PMID: 36168813 DOI: 10.1039/d2cp01987f] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Direct dynamic simulations have been employed to investigate the OH- + CH3Cl reaction with the chosen B3LYP/aug-cc-pVDZ method. The calculated rate coefficient for the bimolecular nucleophilic substitution reaction (SN2), 1.0 × 10-9 cm3 mol-1 s-1 at 300 K, agrees well with the experimental result of (1.3-1.6) × 10-9 cm3 mol-1 s-1. The simulations reveal that the majority of the SN2 reactions are temporarily trapped in the hydrogen-bonded complex at Ecoll = 0.89 kcal mol-1. Importantly, the influences of the leaving group and nucleophile have been discussed by comparisons of X- + CH3Y (X = F, OH; Y = Cl, I) reactions. For the X = F- reactions, the reaction probability of SN2 increases along the increased leaving group ability Cl < I, suggesting that the thermodynamic factor plays a key role. The indirect mechanisms were found to be dominant for both reactions. In contrast, for X = OH-, the fraction of SN2 drops with the enhanced leaving group ability. In particular, a dramatic transition occurs for the dominant atomic reaction mechanisms, i.e., from complex-mediated indirect to direct, implying an interesting contest between the leaving group and the nucleophile and the importance of the dynamic factors, i.e., the dipole moment, steric hindrance, and electronegativity.
Collapse
Affiliation(s)
- Siwei Zhao
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.
| | - Gang Fu
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.
| | - Wenqing Zhen
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.
| | - Li Yang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. .,State Key Lab of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Jianmin Sun
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. .,State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150001, P. R. China
| | - Jiaxu Zhang
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China. .,State Key Lab of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, P. R. China
| |
Collapse
|
7
|
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.
Collapse
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
| |
Collapse
|
8
|
Tachikawa H. Reaction mechanism of an intracluster S N2 reaction induced by electron capture. Phys Chem Chem Phys 2022; 24:3941-3950. [PMID: 35098286 DOI: 10.1039/d1cp04697g] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Bimolecular nucleophilic substitution (SN2) reactions have been widely investigated from both experimental and theoretical points of view because they represent one of the simplest organic reactions. Most studies on SN2 reactions have been focused on bimolecular collision. In contrast, information on intracluster SN2 reactions is limited. In this study, an intracluster SN2 reaction of NF3-CH3Cl triggered by electron attachment was investigated using a direct ab initio molecular dynamics (AIMD) method. In the structure of NF3-CH3Cl, the N-F bond in NF3 is oriented collinearly toward the carbon atom of CH3Cl. After electron capture by NF3-CH3Cl, the F- ion that is generated from the (NF3)- moiety collides with the carbon atom of CH3Cl. The intracluster SN2 reaction occurs as follows: (NF3-CH3Cl)- (electron capture state) → NF2-(F-)-CH3Cl (pre-reaction complex) → transition state (TS) → NF2-CH3F-Cl- (post-reaction complex) → NF2 + CH3F + Cl- (product state). The reaction energy is efficiently transferred to the translational mode of Cl-, and the Cl- ion with a high translational energy is then removed from the system. This energy is significantly larger than that of Cl- formed in the bimolecular SN2 reaction (F- + CH3Cl). The reaction mechanism is discussed based on the theoretical results.
Collapse
Affiliation(s)
- Hiroto Tachikawa
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
| |
Collapse
|
9
|
Wester R. Fifty years of nucleophilic substitution in the gas phase. MASS SPECTROMETRY REVIEWS 2021; 41:627-644. [PMID: 34060119 PMCID: PMC9291629 DOI: 10.1002/mas.21705] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/05/2021] [Accepted: 05/05/2021] [Indexed: 06/12/2023]
Abstract
Bimolecular nucleophilic substitution ( S N 2 ) reactions have become a model system for the investigation of structure-reactivity relationships, stereochemistry, solvent influences, and detailed atomistic dynamics. In this review, the progress during five decades of experimental and theoretical research on gas phase S N 2 reactions is discussed. Many advancements of the employed methods have led to a tremendous increase in our understanding of the properties and the dynamics of these reactions. For reactions involving six atoms a quantitative agreement of the differential reactive scattering cross sections has already been achieved, in the future it is expected that even larger polyatomic reactions systems become tractable. Furthermore, studies with higher precision, improved reactant control, and a more accurate theoretical treatment of quantum effects are envisioned.
Collapse
Affiliation(s)
- Roland Wester
- Institut für Ionenphysik und Angewandte PhysikUniversität InnsbruckTechnikerstraße 256020 InnsbruckAustria
| |
Collapse
|
10
|
Ji X, Zhao C, Xie J. Investigating the role of halogen-bonded complexes in microsolvated Y−(H2O)n + CH3I SN2 reactions. Phys Chem Chem Phys 2021; 23:6349-6360. [DOI: 10.1039/d0cp06299e] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A halogen-bonded complex pathway is computed for Y−(H2O)n + CH3I (Y = HO, F, Cl, Br, and I) ion–molecule nucleophilic substitution reactions and is compared with back-side and front-side attack pathways.
Collapse
Affiliation(s)
- Xiaoyan Ji
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
| | - Chongyang Zhao
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
| | - Jing Xie
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
| |
Collapse
|
11
|
Dobulis MA, Thompson MC, Sommerfeld T, Jarrold CC. Temporary anion states of fluorine substituted benzenes probed by charge transfer in O 2 -·C 6H 6-xF x (x = 0-5) ion-molecule complexes. J Chem Phys 2020; 152:204309. [PMID: 32486698 DOI: 10.1063/5.0011321] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The broadband photoelectron source realized by detaching O2 -·X (X = neutral unsaturated molecule) complexes offers a unique opportunity to probe temporary anion states of the unsaturated species. Detachment of the ion molecule complex typically accesses a dissociative portion of the neutral potential, creating a continuum electron source that can undergo scattering with X. We present the application of this new approach to electron-neutral scattering toward a study of the series of fluorinated benzenes via photoelectron spectroscopy of O2 -·C6H6-xFx (x = 0-6) measured with several photon energies. We compare these spectra to the reference O2 -·hexane spectrum and observe evidence of temporary anion states of C6H6-xFx for species with x = 0-5 in the form of enhanced signal intensity at electron kinetic energies coinciding with the energies of the temporary anions. Furthermore, we observe autodetachment features in the x = 3, 5 spectra. Results of calculations on the isolated symmetric isomer of C6H3F3 suggest that the molecule cannot support a weakly-bound non-valence state that could be associated with the observed autodetachment. However, C6HF5 - is predicted to support a valence bound state, which, if produced by charge transfer from O2 - with sufficient vibrational energy, may undergo autodetachment. Finally, the [O2·C6F6]- spectrum is unique insofar as the spectrum is substantially higher in binding energy and qualitatively different from the x = 0-5 spectra. This result suggests much stronger interactions and charge delocalization between O2 - and C6F6.
Collapse
Affiliation(s)
- Marissa A Dobulis
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA
| | - Michael C Thompson
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA
| | - Thomas Sommerfeld
- Department of Chemistry and Physics, Southeast Louisiana University, SLU 10878, Hammond, Louisiana 70402, USA
| | - Caroline Chick Jarrold
- Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, USA
| |
Collapse
|
12
|
Gregory J, Verlet JRR, Bull JN. Spectroscopic characterisation of radical polyinterhalogen molecules. Phys Chem Chem Phys 2020; 22:8284-8288. [PMID: 32270847 DOI: 10.1039/d0cp01311k] [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
Spectroscopic characterisations of the radical polyinterhalogen molecules IF2 and I2F are reported using anion photoelectron spectroscopy. The corresponding parent anions, IF2- and I2F-, are common products formed in hard Ar-CF3I plasmas and are relevant in the semiconductor manufacture industry. The I2F- species, which is present as the [I-I-F]- isomer, is a "non-classical" polyinterhalogen.
Collapse
Affiliation(s)
- Joe Gregory
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, UK.
| | - Jan R R Verlet
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, UK
| | - James N Bull
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, UK.
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
Czakó G, Győri T, Olasz B, Papp D, Szabó I, Tajti V, Tasi DA. Benchmark ab initio and dynamical characterization of the stationary points of reactive atom + alkane and SN2 potential energy surfaces. Phys Chem Chem Phys 2020; 22:4298-4312. [DOI: 10.1039/c9cp04944d] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We review composite ab initio and dynamical methods and their applications to characterize stationary points of atom/ion + molecule reactions.
Collapse
Affiliation(s)
- Gábor Czakó
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Tibor Győri
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Balázs Olasz
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Dóra Papp
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - István Szabó
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Viktor Tajti
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| | - Domonkos A. Tasi
- MTA-SZTE Lendület Computational Reaction Dynamics Research Group
- Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science
- Institute of Chemistry
- University of Szeged
- Szeged H-6720
| |
Collapse
|
15
|
Chipanina NN, Lazareva NF, Oznobikhina LP, Shainyan BA. Tetrel Bonding along the Pathways of Transsilylation and Alkylation of N-Trimethylsilyl-N-methylacetamide with Bifunctional (Chloromethyl)fluorosilanes. J Phys Chem A 2019; 123:5178-5189. [DOI: 10.1021/acs.jpca.9b03876] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nina N. Chipanina
- A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of the Russian Academy of Sciences, 1 Favorsky Street, 664033 Irkutsk, Russian Federation
| | - Nataliya F. Lazareva
- A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of the Russian Academy of Sciences, 1 Favorsky Street, 664033 Irkutsk, Russian Federation
| | - Larisa P. Oznobikhina
- A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of the Russian Academy of Sciences, 1 Favorsky Street, 664033 Irkutsk, Russian Federation
| | - Bagrat A. Shainyan
- A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of the Russian Academy of Sciences, 1 Favorsky Street, 664033 Irkutsk, Russian Federation
| |
Collapse
|
16
|
Abstract
Electron attachment onto water clusters to form water cluster anions is studied by varying the point of electron attachment along a molecular beam axis and probing the produced cluster anions using photoelectron spectroscopy. The results show that the point of electron attachment has a clear effect on the final distribution of isomers for a cluster containing 78 water molecules, with isomer I formed preferentially near the start of the expansion and isomer II formed preferentially once the molecular beam has progressed for several millimeters. These changes can be accounted for by the cluster growth rate along the beam. Near the start of the expansion, cluster growth is proceeding rapidly with condensing water molecules solvating the electron, while further along the expansion, the growth has terminated and electrons are attached to large and cold preformed clusters, leading to the isomer associated with a loosely bound surface state.
Collapse
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
| |
Collapse
|