1
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Fixot B, Louaas E, Bonhommeau DA. Collision of rare-gas atoms on helium nanodroplets: Theoretical evidence for an efficient coagulation of heavy rare-gas atoms. J Chem Phys 2024; 161:044307. [PMID: 39051833 DOI: 10.1063/5.0220027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 07/08/2024] [Indexed: 07/27/2024] Open
Abstract
The coagulation of rare-gas atoms (RG = Ne, Ar, Kr, Xe, and Rn) in helium nanodroplets (HNDs) composed of 1000 atoms is investigated by zero-point averaged dynamics where a He-He pseudopotential is used to make the droplet liquid with proper energies. This method reproduces the qualitative abundances of embedded Arn+1 structures obtained by Time-Dependent Density Functional Theory and Ring Polymer Molecular Dynamics for Ar + ArnHe1000 collisions at realistic projectile speeds and impact parameters. More generally, coagulation is found to be much more efficient for heavy rare-gases (Xe and Rn) than for light ones (Ne and Ar), a behavior mainly attributed to a slower energy dissipation of the projectile in the HND. When coagulation does not occur, the projectile maintains a speed of 10-30 m s-1 within the HND, but its velocity vector is rarely oriented toward the dopant, and the projectile roams in a limited region of the droplet. The structure of embedded RGn+1 clusters does not systematically match their gas-phase global minimum structure, and more than 30% of RGn-RG unbound structures are due to one He atom located in between the projectile and a dopant atom.
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Affiliation(s)
- Brendan Fixot
- Université Paris-Saclay, Univ Evry, CY Cergy Paris Université, CNRS, LAMBE, Evry-Courcouronnes 91025, France
| | - Elsa Louaas
- Université Paris-Saclay, Univ Evry, CY Cergy Paris Université, CNRS, LAMBE, Evry-Courcouronnes 91025, France
| | - David A Bonhommeau
- Université Paris-Saclay, Univ Evry, CY Cergy Paris Université, CNRS, LAMBE, Evry-Courcouronnes 91025, France
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2
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Vilà A, González M. Quantum dynamics of the Br 2 (B-excited state) photodissociation in superfluid helium nanodroplets: importance of the recombination process. Phys Chem Chem Phys 2022; 24:24353-24361. [PMID: 36178095 DOI: 10.1039/d2cp02984g] [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
We have studied the Br2 photodissociation dynamics (B ← X electronic transition) of Br2(v = 0, X)@(4He)N doped nanodroplets (T = 0.37 K) at zero angular momentum, with N in the 100-1000 interval. To do this, we have used a quantum mechanical hybrid strategy proposed by us and, as far as we know, this is the second quantum dynamics study available on the photodissociation of molecules in superfluid helium nanodroplets. While the results obtained for some properties are qualitatively similar to those reported previously by us for the Cl2(B ← X) related case (in particular, the oscillating Br final velocity distribution which also arises from quantum interferences), large differences are evident in three key properties: the photodissociation mechanism and probability and the time scale of the process. This can be interpreted on the basis of the significantly lower excitation energy achieved by the Br2(B ← X) transition and the higher reduced mass of Br-Br in comparison to the chlorine case. The Br2(B) photodissociation dynamics is significantly more complex than that of Cl2(B) and leads to the fragmentation of the initial wave packet. Thus, the probability of non-dissociation is equal to 17, 18, 51, 85 and 100% for N = 100, 200, 300, 500 and 1000, respectively, while for chlorine this probability is equal to zero. In spite of the very large experimental difficulties that exist for obtaining nanodroplets with a well defined size, we hope that these results will encourage experimentalists to investigate these interesting systems.
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Affiliation(s)
- Arnau Vilà
- Departament de Ciència dels Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
| | - Miguel González
- Departament de Ciència dels Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
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3
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Panzou R, Lewerenz M. Photofragmentation of I2 molecules inside helium clusters: model calculations using a quantum effective potential. Mol Phys 2021. [DOI: 10.1080/00268976.2021.1977862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Roland Panzou
- Laboratoire Modélisation et Simulation Multi Echelle, MSME, Univ. Gustave Eiffel, CNRS UMR 8208, Univ. Paris Est Créteil, Marne-la-Vallée, France
| | - Marius Lewerenz
- Laboratoire Modélisation et Simulation Multi Echelle, MSME, Univ. Gustave Eiffel, CNRS UMR 8208, Univ. Paris Est Créteil, Marne-la-Vallée, France
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4
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Fischer J, Schlaghaufer F, Lottner EM, Slenczka A, Christiansen L, Stapelfeldt H, Karra M, Friedrich B, Mullan T, Schütz M, Usvyat D. Heterogeneous Clusters of Phthalocyanine and Water Prepared and Probed in Superfluid Helium Nanodroplets. J Phys Chem A 2019; 123:10057-10064. [PMID: 31670512 DOI: 10.1021/acs.jpca.9b07302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Superfluid helium nanodroplets comprised of thousands to millions of helium atoms can serve as a reactor for the synthesis of heterogeneous molecular clusters at cryogenic conditions. The cluster synthesis occurs via consecutive pick-up of the cluster building blocks by the helium droplet and their subsequent coalescence within the droplet. The effective collision cross section of the building blocks is determined by the helium droplet size and thus exceeds by orders of magnitude that of a reactive collision in the gas phase. Moreover, the cryogenic helium environment (at 0.38 K) as a host promotes the formation of metastable cluster configurations. The question arises as to the extent of the actual involvement of the helium environment in the cluster formation. The present study deals with clusters of single phthalocyanine (Pc) molecules with single water molecules. A large fluorophore such as Pc offers several sites where the water molecule can attach. The resulting isomeric variants of the Pc-H2O complex can be selectively identified by electronic spectroscopy. We compare the experimental electronic spectra of the Pc-H2O complex generated in superfluid helium nanodroplets with the results of quantum-chemical calculations on the same cluster but under gas-phase conditions. The number of isomeric variants observed in the helium droplet experiment comes out the same as that obtained from our gas-phase calculations.
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Affiliation(s)
- J Fischer
- Institut für Physikalische und Theoretische Chemie , Universität Regensburg , 93053 Regensburg , Germany
| | - F Schlaghaufer
- Institut für Physikalische und Theoretische Chemie , Universität Regensburg , 93053 Regensburg , Germany
| | - E-M Lottner
- Institut für Physikalische und Theoretische Chemie , Universität Regensburg , 93053 Regensburg , Germany
| | - A Slenczka
- Institut für Physikalische und Theoretische Chemie , Universität Regensburg , 93053 Regensburg , Germany
| | - L Christiansen
- Department of Chemistry , Aarhus University , Langelandsgade 140 , 8000 Aarhus C , Denmark
| | - H Stapelfeldt
- Department of Chemistry , Aarhus University , Langelandsgade 140 , 8000 Aarhus C , Denmark
| | - M Karra
- Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany
| | - B Friedrich
- Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany
| | - Th Mullan
- Institut für Chemie , Humboldt-Universität zu Berlin , Unter den Linden 6 , 10099 Berlin , Germany
| | - M Schütz
- Institut für Chemie , Humboldt-Universität zu Berlin , Unter den Linden 6 , 10099 Berlin , Germany
| | - D Usvyat
- Institut für Chemie , Humboldt-Universität zu Berlin , Unter den Linden 6 , 10099 Berlin , Germany
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5
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Blancafort-Jorquera M, Vilà A, González M. Quantum-classical approach to the reaction dynamics in a superfluid helium nanodroplet. The Ne 2 dimer and Ne-Ne adduct formation reaction Ne + Ne-doped nanodroplet. Phys Chem Chem Phys 2019; 21:24218-24231. [PMID: 31661098 DOI: 10.1039/c9cp04561a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of the Ne2 dimer and Ne-Ne adduct formation in a superfluid helium nanodroplet [(4He)N; T = 0.37 K], Ne + Ne@(4He)N→ Ne2@(4He)N'/Ne-Ne@(4He)N' + (N-N')4He with N = 500, has been investigated using a hybrid approach (quantum and classical mechanics (QM-CM) descriptions for helium and the Ne atoms, respectively) and taking into account the angular momentum of the attacking Ne atom, Ne(1). Comparison with zero angular momentum QM results of our own shows that the present results are similar to the quantum ones for the initial Ne(1) velocities (v0) of 500 and 800 m s-1 (the former one being the most probable velocity of Ne at 300 K), in all cases leading to the Ne2 dimer (re = 3.09 Å). However, significant differences appear below v0 = 500 m s-1, because in the QM-CM dynamics, instead of the dimer, a Ne-Ne adduct is formed (r0 = 5.45 Å). The formation of this adduct will probably dominate as the contribution to reactivity of angular momenta larger than zero is the leading one and angular momentum strongly acts against the Ne2 production. Angular momentum adds further difficulties in producing the dimer, since it makes it more difficult to remove the helium density between both Ne atoms to lead, subsequently, to the Ne2 molecule. Hence, the formation of the neon-neon adduct, Ne-Ne@(4He)N', clearly dominates the reactivity of the system, which results in the formation of a "quantum gel"/"quantum foam", because the two Ne atoms essentially maintain their identity inside the nanodroplet. Large enough Ne(1) initial angular momentum values can induce the formation of vortex lines by the collapse of superficial excitations (ripplons), but they occur with greater difficulty than in the case of the capture of the Ne atom by a non doped helium nanodroplet, due to the wave interferences induced by the Ne induced by the solvation layers of the Ne atom originally placed inside the nanodroplet. We hope that this work will encourage other researchers to investigate the reaction dynamics in helium nanodroplets, an interesting topic on which there are few studies available.
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Affiliation(s)
- Miquel Blancafort-Jorquera
- Departament de Ciència de Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
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6
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Blancafort-Jorquera M, Vilà A, González M. Quantum-classical dynamics of the capture of neon atoms by superfluid helium nanodroplets. Phys Chem Chem Phys 2018; 20:29737-29753. [DOI: 10.1039/c8cp05140b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The capture dynamics of Ne by a HeND was studied theoretically in a detailed manner (energy and angular momentum transfer and vortex formation).
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Affiliation(s)
| | - Arnau Vilà
- Departament de Ciència de Materials i Química Física and IQTC
- Universitat de Barcelona
- Barcelona
- Spain
| | - Miguel González
- Departament de Ciència de Materials i Química Física and IQTC
- Universitat de Barcelona
- Barcelona
- Spain
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7
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Ancilotto F, Barranco M, Coppens F, Eloranta J, Halberstadt N, Hernando A, Mateo D, Pi M. Density functional theory of doped superfluid liquid helium and nanodroplets. INT REV PHYS CHEM 2017. [DOI: 10.1080/0144235x.2017.1351672] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Francesco Ancilotto
- Dipartimento di Fisica e Astronomia ‘Galileo Galilei’ and CNISM, Università di Padova, Padova, Italy
- CNR-IOM Democritos, Trieste, Italy
| | - Manuel Barranco
- Facultat de Física, Departament FQA, Universitat de Barcelona, Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain
- Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, Université Toulouse 3 and CNRS, Toulouse Cedex 09, France
| | - François Coppens
- Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, Université Toulouse 3 and CNRS, Toulouse Cedex 09, France
| | - Jussi Eloranta
- Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, CA, USA
| | - Nadine Halberstadt
- Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, Université Toulouse 3 and CNRS, Toulouse Cedex 09, France
| | - Alberto Hernando
- Social Thermodynamics Applied Research (SThAR), EPFL Innovation Park, Lausanne, Switzerland
| | - David Mateo
- Applied Complexity Group, Singapore University of Technology and Design, Singapore, Singapore
| | - Martí Pi
- Facultat de Física, Departament FQA, Universitat de Barcelona, Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain
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8
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Shepperson B, Chatterley AS, Søndergaard AA, Christiansen L, Lemeshko M, Stapelfeldt H. Strongly aligned molecules inside helium droplets in the near-adiabatic regime. J Chem Phys 2017; 147:013946. [DOI: 10.1063/1.4983703] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Affiliation(s)
- Benjamin Shepperson
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Adam S. Chatterley
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Anders A. Søndergaard
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Lars Christiansen
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Mikhail Lemeshko
- IST Austria (Institute of Science and Technology Austria), Am Campus 1, 3400 Klosterneuburg, Austria
| | - Henrik Stapelfeldt
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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9
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Vilà A, González M. Mass effects in the photodissociation of homonuclear diatomic molecules in helium nanodroplets: inelastic collision and viscous flow energy exchange regimes. Phys Chem Chem Phys 2016; 18:27630-27638. [DOI: 10.1039/c6cp04315a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photodissociation of a diatomic molecule X2 in a superfluid helium nanodroplet presents two sequential dynamic regimes: the starting perfectly inelastic collision followed by the viscous flow. This mechanism has probably general character.
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Affiliation(s)
- Arnau Vilà
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Miguel González
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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10
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Vilà A, González M. Reaction dynamics inside superfluid helium nanodroplets: the formation of the Ne2 molecule from Ne + Ne@(4He)N. Phys Chem Chem Phys 2016; 18:31869-31880. [DOI: 10.1039/c6cp03942a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A hybrid TDDFT approach was proposed to consider bimolecular reactive processes in superfluid helium nanodroplets. The Ne + Ne@(4He)N reaction was considered as the first application example. The formation of Ne2 is a complex process related to the nature of the helium density waves and their reflection from the nanodroplet surface.
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Affiliation(s)
- Arnau Vilà
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Miguel González
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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11
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Vilà A, González M, Mayol R. Quantum dynamics of the pick up process of atoms by superfluid helium nanodroplets: the Ne + (4He)1000 system. Phys Chem Chem Phys 2016; 18:2006-14. [DOI: 10.1039/c5cp04176g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The quantum dynamics of neon atom capture by a superfluid helium-4 nanodroplet has been theoretically investigated using a hybrid method.
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Affiliation(s)
- Arnau Vilà
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Miguel González
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Ricardo Mayol
- Departament d'Estructura i Constituents de la Matèria
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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12
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Vilà A, González M, Mayol R. Photodissociation Dynamics of Homonuclear Diatomic Molecules in Helium Nanodroplets. The Case of Cl2@(4He)N. J Chem Theory Comput 2015; 11:899-906. [DOI: 10.1021/ct5011642] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Arnau Vilà
- Departament
de Química Física i IQTC and ‡Departament d’Estructura
i Constituents de la Matèria, Universitat de Barcelona, c/Martí
i Franquès, 1, 08028 Barcelona, Spain
| | - Miguel González
- Departament
de Química Física i IQTC and ‡Departament d’Estructura
i Constituents de la Matèria, Universitat de Barcelona, c/Martí
i Franquès, 1, 08028 Barcelona, Spain
| | - Ricardo Mayol
- Departament
de Química Física i IQTC and ‡Departament d’Estructura
i Constituents de la Matèria, Universitat de Barcelona, c/Martí
i Franquès, 1, 08028 Barcelona, Spain
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13
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Vilà A, González M, Mayol R. Quantum interferences in the photodissociation of Cl2(B) in superfluid helium nanodroplets (4He)N. Phys Chem Chem Phys 2015; 17:32241-50. [DOI: 10.1039/c5cp03575a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The origin of quantum interferences theoretically found in the photodissociation of chlorine in superfluid 4He nanodroplets was investigated in detail.
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Affiliation(s)
- Arnau Vilà
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Miguel González
- Departament de Química Física i IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Ricardo Mayol
- Departament d’Estructura i Constituents de la Matèria
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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14
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Reid SA. When isomerisation is electron transfer: the intriguing story of the iso-halocarbons. INT REV PHYS CHEM 2014. [DOI: 10.1080/0144235x.2014.942548] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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15
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Zhang C, Zhang Z, Huang C, Zhang Q, Chen Y. Helium Droplets: An Apparatus to Study Ultra Cold Chemistry. CHINESE J CHEM PHYS 2013. [DOI: 10.1063/1674-0068/26/03/270-276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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16
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Hernando A, Barranco M, Pi M, Loginov E, Langlet M, Drabbels M. Desorption of alkali atoms from 4He nanodroplets. Phys Chem Chem Phys 2012; 14:3996-4010. [DOI: 10.1039/c2cp23526a] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Chichinin AI, Gericke KH, Kauczok S, Maul C. Imaging chemical reactions – 3D velocity mapping. INT REV PHYS CHEM 2009. [DOI: 10.1080/01442350903235045] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Bonhommeau D, Lewerenz M, Halberstadt N. Fragmentation of ionized doped helium nanodroplets: theoretical evidence for a dopant ejection mechanism. J Chem Phys 2008; 128:054302. [PMID: 18266445 DOI: 10.1063/1.2823101] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report a theoretical study of the effect induced by a helium nanodroplet environment on the fragmentation dynamics of a dopant. The dopant is an ionized neon cluster Ne(n) (+) (n=4-6) surrounded by a helium nanodroplet composed of 100 atoms. A newly designed mixed quantum/classical approach is used to take into account both the large helium cluster zero-point energy due to the light mass of the helium atoms and all the nonadiabatic couplings between the Ne(n) (+) potential-energy surfaces. The results reveal that the intermediate ionic dopant can be ejected from the droplet, possibly with some helium atoms still attached, thereby reducing the cooling power of the droplet. Energy relaxation by helium atom evaporation and dissociation, the other mechanism which has been used in most interpretations of doped helium cluster dynamics, also exhibits new features. The kinetic energy distribution of the neutral monomer fragments can be fitted to the sum of two Boltzmann distributions, one with a low kinetic energy and the other with a higher kinetic energy. This indicates that cooling by helium atom evaporation is more efficient than was believed so far, as suggested by recent experiments. The results also reveal the predominance of Ne(2) (+) and He(q)Ne(2) (+) fragments and the absence of bare Ne(+) fragments, in agreement with available experimental data (obtained for larger helium nanodroplets). Moreover, the abundance in fragments with a trimeric neon core is found to increase with the increase in dopant size. Most of the fragmentation is achieved within 10 ps and the only subsequent dynamical process is the relaxation of hot intermediate He(q)Ne(2) (+) species to Ne(2) (+) by helium atom evaporation. The dependence of the ionic fragment distribution on the parent ion electronic state reached by ionization is also investigated. It reveals that He(q)Ne(+) fragments are produced only from the highest electronic state, whereas He(q)Ne(2) (+) fragments originate from all the electronic states. Surprisingly, the highest electronic states also lead to fragments that still contain the original ionic dopant species. A mechanism is conjectured to explain this fragmentation inhibition.
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Affiliation(s)
- D Bonhommeau
- University of Minnesota, 207 Pleasant Street S.E., 230 Smith Hall, Minneapolis, Minnesota 55455-0431, USA
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19
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Loginov E, Braun A, Drabbels M. A new sensitive detection scheme for helium nanodroplet isolation spectroscopy: application to benzene. Phys Chem Chem Phys 2008; 10:6107-14. [DOI: 10.1039/b808211a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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