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Schmidt S, Plamper D, Jekkel J, Weitzel KM. Self-Reactions in the HBr + (DBr +) + HBr System: A State-Selective Investigation of the Role of Rotation. J Phys Chem A 2020; 124:8461-8468. [PMID: 32960596 DOI: 10.1021/acs.jpca.0c07361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Self-reactions observed in the HBr+ (DBr+) + HBr system have been investigated using a guided ion-beam experiment under single-collision conditions. The reaction channels observed are proton transfer/hydrogen abstraction (PT/HA) in the case of HBr+ and deuteron transfer/hydrogen abstraction (DT/HA) and charge transfer (CT) in the case of DBr+. HBr+/DBr+ ions have been formed with rotational energies selected using the resonance-enhanced multiphoton ionization (REMPI) formation process. Cross sections have been measured as a function of the rotational energy of the ion, Erot, and of the center-of-mass collision energy, Ecm. In the region of low rotational energies, the cross section for both PT/HA and DT/HA decreases with increasing ion rotation. In this region, the cross section for CT increases with increasing ion rotation. For higher rotational energies, the cross section increases with increasing ion rotation for PT/HA and less pronounced for DT/HA. The cross section for CT becomes independent of ion rotation for high rotational energies. Since all reaction channels are exothermic, all cross sections decrease with increasing Ecm.
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Affiliation(s)
- Sebastian Schmidt
- Philipps-Universität Marburg, Fachbereich Chemie, Marburg 35032, Germany
| | - Dominik Plamper
- Philipps-Universität Marburg, Fachbereich Chemie, Marburg 35032, Germany
| | - Jasmin Jekkel
- Philipps-Universität Marburg, Fachbereich Chemie, Marburg 35032, Germany
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2
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Uhlemann T, Wallauer J, Weitzel KM. Self-reactions in the HCl+ (DCl+) + HCl system: a state-selective investigation of the role of rotation. Phys Chem Chem Phys 2015; 17:16454-61. [DOI: 10.1039/c5cp02266e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cross sections for the self-reaction of state-selected HCl+ (DCl+) ions with HCl are shown to depend characteristically on the rotational velocity of the ion relative to that of the neutral.
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Affiliation(s)
- Till Uhlemann
- Philipps-Universität Marburg
- Fachbereich Chemie
- Marburg
- Germany
| | - Jens Wallauer
- Philipps-Universität Marburg
- Fachbereich Chemie
- Marburg
- Germany
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3
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Su Q, Han Y, Cong SL. Quantum control of multi-photon dissociation of HCl+ with intense femtosecond laser pulses. J Chem Phys 2013; 138:024304. [DOI: 10.1063/1.4773022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Deb N, Heazlewood BR, Bell MT, Softley TP. Blackbody-mediated rotational laser cooling schemes in MgH+, DCl+, HCl+, LiH and CsH. Phys Chem Chem Phys 2013; 15:14270-81. [DOI: 10.1039/c3cp51839f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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Korolkov MV, Weitzel KM. Femtosecond interferometry of molecular dynamics – the role of relative and absolute phase of two individual laser pulses. Z PHYS CHEM 2011. [DOI: 10.1524/zpch.2011.0154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Dynamical implications of the dissociation of a molecular ion under the influence of interferometrically generated light fields have been investigated by numerical solution of time dependent Schrödinger equations. As an example the dissociation of DCl+ ions by means of two interfering 7 fs laser pulses at 800 nm has been chosen. We demonstrate that product branching ratios D+:Cl+ can be manipulated from 10:1 to 1:10 not only by adjusting the appropriate delay time in the time-shifted two-pulse approach, but also by choosing the proper carrier envelope phase (CEP) of the two partial light fields. The effects of the phase shift related to the time shift and that of the CEP can be clearly distinguished.
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Weitzel KM. Bond-dissociation energies of cations--pushing the limits to quantum state resolution. MASS SPECTROMETRY REVIEWS 2011; 30:221-235. [PMID: 21337598 DOI: 10.1002/mas.20276] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 07/21/2009] [Accepted: 07/21/2009] [Indexed: 05/30/2023]
Abstract
Currently available concepts for measuring the bond-dissociation energy of cations D(o) are reviewed. Starting from the traditional approach of directly measuring the threshold energy for the appearance of fragment ions, attention is directed towards indirect measurements, where threshold energies are obtained by extrapolation of, for example, rate constants k(E) or kinetic energy release (KER) data to the threshold of interest. More recent high precision techniques again utilize direct measurements, for example, of the disappearance energy of the parent ion. Most precise data are obtained from quantum state resolved measurements of the dissociation energy, where the threshold energy is bracketed by the existing quantum states above and below the threshold. Ultimately the limits can even be pushed beyond the bracketing limit, by investigating steps on the lineshape of homogeneously broadened single rotational transitions.
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Paetow L, Unger F, Beutel B, Weitzel KM. Rotational dependence of the proton-transfer reaction HBr+ + CO2 → HOCO+ + Br. II. Comparison of HBr+ (2Π(3/2)) and HBr+ (2Π(1/2)). J Chem Phys 2010; 133:234301. [PMID: 21186865 DOI: 10.1063/1.3515300] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The effects of reactant ion rotational excitation on the exothermic proton-transfer reactions of HBr(+)((2)Π(1/2)) and DBr(+)((2)Π(1/2)), respectively, with CO(2) were studied in a guided ion beam apparatus. Cross sections are presented for collision energies in the center of mass system E(c.m.) in the range of 0.23 to 1.90 eV. The HBr(+)/DBr(+) ions were prepared in a state-selective manner by resonance enhanced multiphoton ionization. The mean rotational energy was varied from 3.4 to 46.8 meV for HBr(+)((2)Π(1/2)) and from 1.8 to 40.9 meV for DBr(+)((2)Π(1/2)). Both reactions studied are inhibited by collision energy, as expected for exothermic reactions. For all collision energies considered, the cross section decreases with increasing rotational energy of the ion, but the degree of the rotational dependence differs depending on the collision energy. For E(c.m.) = 0.31 eV, the cross sections of the deuteron transfer are significantly larger than those of the proton transfer. For higher E(c.m.) they differ very little. The current results for the exothermic proton transfer are systematically compared to previously published data for the endothermic proton transfer starting from HBr(+)((2)Π(3/2)) [L. Paetow et al., J. Chem. Phys. 132, 174305 (2010)]. Additional new data regarding the latter reaction are presented to further confirm the conclusions. The dependences on rotational excitation found cannot be explained by the corresponding change in the total energy of the system. For both the endothermic and the exothermic reaction, the cross section is maximized for the smallest rotational energy, at least well above the threshold.
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Affiliation(s)
- Lisa Paetow
- Philipps-Universität Marburg, Fachbereich Chemie, Hans-Meerwein-Straβe, 35032 Marburg, Germany
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Paetow L, Unger F, Beichel W, Frenking G, Weitzel KM. Rotational dependence of the proton-transfer reaction HBr++CO2→HOCO++Br. I. Energy versus angular momentum effects. J Chem Phys 2010; 132:174305. [DOI: 10.1063/1.3409734] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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9
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Control of competing dissociation channels by femtosecond interferometry: Aspects of electron and nuclear dynamics. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.01.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Gurin VS, Korolkov MV, Matulis VE, Rakhmanov SK. Symmetry-adapted-cluster configuration interaction study of the doublet states of HCl+: Potential energy curves, dipole moments, and transition dipole moments. J Chem Phys 2007; 126:124321. [PMID: 17411137 DOI: 10.1063/1.2710260] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electronic structure of the HCl(+) molecular ion has been calculated using the general-R symmetry-adapted-cluster configuration interaction (SAC-CI) method. The authors present the potential energy curves, dipole moments, and transition dipole moments for a series of doublet states. The data are compared with the previous CASSCF and MCSCF calculations. The SAC-CI results reproduce quite well the data available in literature and extend the knowledge on the HCl(+) electronic structure for several higher states. The calculated R-dependent behavior of both dipole moments and transition dipole moments for a series of bound and unbound states reveals an intricate dissociation process at intermediate distances (R>R(e)). The pronounced maxima in transition dipole moment (TDM) describing transitions into high electronic states (X (2)Pi-->3 (2)Pi, X (2)Pi-->3 (2)Sigma, 2 (2)Pi-->3 (2)Pi, 3 (2)Pi-->4 (2)Pi) occur at different interatomic separations. Such TDM features are promising for selection of excitation pathways and, consequently, for an optimal control of the dissociation products.
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Affiliation(s)
- Valerij S Gurin
- Physico-Chemical Research Institute, Belarusian State University, Leningradskaya Street 14, 220050 Minsk, Belarus
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Webb AD, Nahler NH, Dixon RN, Ashfold MNR. A velocity map imaging study of the one and two photon dissociations of state-selected DCl+ cations. J Chem Phys 2006; 125:204312. [PMID: 17144705 DOI: 10.1063/1.2390714] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
DCl(+)(X (2)Pi(32),v(+")=0) cations have been prepared by 2+1 resonance enhanced multiphoton ionization, and their subsequent fragmentation following excitation at numerous wavelengths in the range of 240-350 nm studied by velocity map imaging of the resulting Cl(+) products. This range of excitation wavelengths allows selective population of A (2)Sigma(+) state levels with all vibrational (v(+')) quantum numbers in the range 0< or =v(+')< or =15. Image analysis yields wavelength dependent branching ratios and recoil anisotropies of the various D+Cl(+) ((3)P(J), (1)D, and (1)S) product channels. Levels with 10< or =v(+')< or =15 have sufficient energy to predissociate, forming D+Cl(+)((3)P(J)) products with perpendicular recoil anisotropies-consistent with the A (2)Sigma(+)<--X (2)Pi parent excitation and subsequent fragmentation on a time scale that is fast compared with the parent rotational period. Branching into the various spin-orbit states of the Cl(+)((3)P(J)) product is found to depend sensitively upon v(+') and, in the case of the v(+')=13 level, to vary with the precise choice of excitation wavelength within the A (2)Sigma(+)<--X (2)Pi(13,0) band. Such variations have been rationalized qualitatively in terms of the differing contributions made to the overall predissociation rate of DCl(+)(A,v(+')) molecules by coupling to repulsive states of (4)Pi, (4)Sigma(-), and (2)Sigma(-) symmetries, all of which are calculated to cross the outer limb of the A (2)Sigma(+) state potential at energies close to that of the v(+')=10 level. Cl(+)((3)P(J)) fragments are detected weakly following excitation to A (2)Sigma(+) state levels with v(+')=0 or 1, Cl(+)((1)D) fragments dominate the ion yield when exciting via 2< or =v(+')< or =6 and via v(+')=9, while Cl(+)((1)S) fragments dominate the Cl(+) images obtained when exciting via levels with v(+')=7 and 8. Analysis of wavelength resolved action spectra for forming these Cl(+) ions and of the resulting Cl(+) ion images shows that (i) these ions all arise via two photon absorption processes, resonance enhanced at the one photon energy by the various A(v(+')<10) levels, (ii) the first A (2)Sigma(+)<--X (2)Pi absorption step is saturated under the conditions required to observe significant two photon dissociation, and (iii) the final absorption step from the resonance enhancing A(v(+')) level involves a parallel transition.
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Affiliation(s)
- Alexander D Webb
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
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Korolkov MV, Weitzel KM. On the Competition between Predissociation and Direct Dissociation in Deuterium Chloride Ions (DCl+). J Chem Theory Comput 2006; 2:1492-8. [DOI: 10.1021/ct600217t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mikhail V. Korolkov
- Stephanov Institute of Physics, National Academy of Science, Nezavisimosti ave. 70, 220602 Mink, Republic of Belarus, and Philipps Universität Marburg, Fachbereich Chemie, Hans Meerwein Strasse, 35032 Marburg, Germany
| | - Karl-Michael Weitzel
- Stephanov Institute of Physics, National Academy of Science, Nezavisimosti ave. 70, 220602 Mink, Republic of Belarus, and Philipps Universität Marburg, Fachbereich Chemie, Hans Meerwein Strasse, 35032 Marburg, Germany
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Korolkov MV, Weitzel KM. Kinetic and dynamic aspects of lifetime oscillations in the predissociation of hydrogen chloride ions. J Phys Chem A 2006; 110:2924-32. [PMID: 16509614 DOI: 10.1021/jp054365n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The predissociation dynamics of hydrogen chloride ions (HCl+ and DCl+) in the electronic A 2Sigma+ state has been investigated by solving the time dependent Schrödinger equation. The predissociation lifetime is shown to strongly depend on the vibrational and the rotational quantum number, with quasi-periodic oscillations. Rovibronic states, which exhibit lifetimes about 1 order of magnitude larger than those of neighboring states, are termed rotational islands of stability (RIS). These RIS can be correlated with characteristic reference energies, e.g., the difference between rovibronic eigenenergy and the energy of crossing of rotronic bound and repulsive potentials. The origin of these RIS is illustrated by model studies of the positions of the nuclear wave functions involved.
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Affiliation(s)
- Mikhail V Korolkov
- Stephanov Institute of Physics, National Academy of Science, Scarina ave. 70, 220602 Minsk, Republic of Belarus
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Bruna PJ, Grein F. The X2Π and A2Σ+states of FH+, ClH+and BrH+: theoretical study of theirg-factors and fine/hyperfine structures. Mol Phys 2006. [DOI: 10.1080/00268970500404380] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Korolkov MV, Weitzel KM. On the control of product yields in the photofragmentation of deuteriumchlorid ions (DCl+). J Chem Phys 2005; 123:164308. [PMID: 16268698 DOI: 10.1063/1.2076687] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The prospect of controlling the photofragmentation of deuterium chloride ions (DCl+) via strong ultrashort IR laser pulses has been investigated by a numerical solution of coupled Schrodinger equations. The calculations provide evidence that the ratio of product ion yields Cl+ versus D+ can be manipulated by an appropriate choice of laser pulse parameters, in particular, central laser frequency, pulse duration, intensity, and chirp. The analysis of time-dependent populations reveals competition between intra- and interelectronic state excitations, enabling the understanding of quantum control at the molecular level.
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Affiliation(s)
- Mikhail V Korolkov
- Stephanov Institute of Physics, National Academy of Science, Republic of Belarus and Philipps Universität Marburg, Fachbereich Chemie, Hans Meerwein Strasse, 35032 Marburg, Germany
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Nolde M, Weitzel KM, Western CM. The resonance enhanced multiphoton ionisation spectroscopy of ammonia isotopomers NH3, NH2D, NHD2 and ND3. Phys Chem Chem Phys 2005; 7:1527-32. [DOI: 10.1039/b417835c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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