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Kösling P, Rüger CP, Schade J, Fort KL, Ehlert S, Irsig R, Kozhinov AN, Nagornov KO, Makarov A, Rigler M, Tsybin YO, Walte A, Zimmermann R. Vacuum Laser Photoionization inside the C-trap of an Orbitrap Mass Spectrometer: Resonance-Enhanced Multiphoton Ionization High-Resolution Mass Spectrometry. Anal Chem 2021; 93:9418-9427. [PMID: 34170684 DOI: 10.1021/acs.analchem.1c01018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
State-of-the-art mass spectrometry with ultraviolet (UV) photoionization is mostly limited to time-of-flight (ToF) mass spectrometers with 1000-10 000 m/Δm mass resolution. However, higher resolution and higher spectral dynamic range mass spectrometry may be indispensable in complex mixture characterization. Here, we present the concept, implementation, and initial evaluation of a compact ultrahigh-resolution mass spectrometer with gas-phase laser ionization. The concept is based on direct laser photoionization in the ion accumulation and ejection trap (C-trap) of an Orbitrap mass spectrometer. Resonance-enhanced multiphoton ionization (REMPI) using 266 nm UV pulses from a frequency-quadrupled Nd:YAG laser was applied for selective and efficient ionization of monocyclic and polycyclic aromatic hydrocarbons. The system is equipped with a gas inlet for volatile compounds and a heated gas chromatography coupling. The former can be employed for rapid system m/z-calibration and performance evaluation, whereas the latter enables analysis of semivolatile and higher-molecular-weight compounds. The capability to evaluate complex mixtures is demonstrated for selected petrochemical materials. In these experiments, several hundred to over a thousand compounds could be attributed with a root-mean-square mass error generally below 1 ppm and a mass resolution of over 140 000 at 200 m/z. Isobaric interferences could be resolved, and narrow mass splits, such as 3.4 mDa (SH4/C3), are determined. Single laser shots provided limits of detection in the 20-ppb range for p-xylene and 1,2,4-trimethylbenzene, similar to compact vacuum REMPI-ToF systems.
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Affiliation(s)
- Paul Kösling
- Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.,Department Life, Light & Matter (LLM), University of Rostock, 18059 Rostock, Germany
| | - Christopher P Rüger
- Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.,Department Life, Light & Matter (LLM), University of Rostock, 18059 Rostock, Germany
| | - Julian Schade
- Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.,Department Life, Light & Matter (LLM), University of Rostock, 18059 Rostock, Germany
| | - Kyle L Fort
- Thermo Fisher Scientific (Bremen) GmbH, 28199 Bremen, Germany
| | - Sven Ehlert
- Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.,Department Life, Light & Matter (LLM), University of Rostock, 18059 Rostock, Germany.,Photonion GmbH, 19061 Schwerin, Germany
| | - Robert Irsig
- Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.,Department Life, Light & Matter (LLM), University of Rostock, 18059 Rostock, Germany.,Photonion GmbH, 19061 Schwerin, Germany
| | | | | | | | | | | | | | - Ralf Zimmermann
- Joint Mass Spectrometry Centre (JMSC)/Chair of Analytical Chemistry, University of Rostock, 18059 Rostock, Germany.,Department Life, Light & Matter (LLM), University of Rostock, 18059 Rostock, Germany.,Joint Mass Spectrometry Centre, Cooperation Group "Comprehensive Molecular Analytics", Helmholtz Zentrum Muenchen, Neuherberg D-85764, Germany
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Adamson BD, Skeen SA, Ahmed M, Hansen N. Detection of Aliphatically Bridged Multi-Core Polycyclic Aromatic Hydrocarbons in Sooting Flames with Atmospheric-Sampling High-Resolution Tandem Mass Spectrometry. J Phys Chem A 2018; 122:9338-9349. [PMID: 30415549 DOI: 10.1021/acs.jpca.8b08947] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This paper provides experimental evidence for the chemical structures of aliphatically substituted and bridged polycyclic aromatic hydrocarbon (PAH) species in gas-physe combustion environments. The identification of these single- and multicore aromatic species, which have been hypothesized to be important in PAH growth and soot nucleation, was made possible through a combination of sampling gaseous constituents from an atmospheric pressure inverse coflow diffusion flame of ethylene and high-resolution tandem mass spectrometry (MS-MS). In these experiments, the flame-sampled components were ionized using a continuous VUV lamp at 10.0 eV and the ions were subsequently fragmented through collisions with Ar atoms in a collision-induced dissociation (CID) process. The resulting fragment ions, which were separated using a reflectron time-of-flight mass spectrometer, were used to extract structural information about the sampled aromatic compounds. The high-resolution mass spectra revealed the presence of alkylated single-core aromatic compounds and the fragment ions that were observed correspond to the loss of saturated and unsaturated units containing up to a total of 6 carbon atoms. Furthermore, the aromatic structures that form the foundational building blocks of the larger PAHs were identified to be smaller single-ring and pericondensed aromatic species with repetitive structural features. For demonstrative purposes, details are provided for the CID of molecular ions at masses 202 and 434. Insights into the role of the aliphatically substituted and bridged aromatics in the reaction network of PAH growth chemistry were obtained from spatially resolved measurements of the flame. The experimental results are consistent with a growth mechanism in which alkylated aromatics are oxidized to form pericondensed ring structures or react and recombine with other aromatics to form larger, potentially three-dimensional, aliphatically bridged multicore aromatic hydrocarbons.
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Affiliation(s)
- B D Adamson
- Combustion Research Facility , Sandia National Laboratories , Livermore , California 94551 , United States
| | - S A Skeen
- Combustion Research Facility , Sandia National Laboratories , Livermore , California 94551 , United States
| | - M Ahmed
- Chemical Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - N Hansen
- Combustion Research Facility , Sandia National Laboratories , Livermore , California 94551 , United States
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Determination of Relative Ionization Cross Sections for Resonance Enhanced Multiphoton Ionization of Polycyclic Aromatic Hydrocarbons. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8091617] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Resonance enhanced multiphoton ionization (REMPI) is a powerful method for the sensitive determination of polycyclic aromatic hydrocarbons (PAHs) in gaseous mixtures via mass spectrometry (MS). In REMPI, ions are produced by the absorption of at least two photons including defined electronic intermediate states. As a result—unlike other laser-based ionization techniques—spectroscopic selectivity is involved into the ionization process. Nevertheless, these wavelength-dependent ionization rates impede the quantification using REMPI. For this purpose, relative photoionization cross sections (relPICS) give an easy-to-use approach to quantify REMPI-MS measurements. Hereby, the ionization behavior of a single compound was compared to that of a reference substance of a given concentration. In this study, relPICS of selected single-core aromatics and PAHs at wavelengths of 266 nm and 248 nm were determined using two different time-of-flight mass spectrometric systems (TOFMS). For PAHs, relPICS were obtained which showed a strong dependence on the applied laser intensity. In contrast, for single-core aromatics, constant values of relPICS were determined. Deviations of relPICS between both TOFMS systems were found for small aromatics (e.g., benzene), which can be assigned to the differences in UV generation in the particular system. However, the relPICS of this study were found to be in good agreement with previous results and can be used for system-independent quantification.
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Alhroub I, Kozliak E, Kubátová A, Sulkes M. PAH/Aromatic Tar and Coke Precursor Formation in the Early Stages of Triglyceride (Triolein) Pyrolysis. J Phys Chem A 2018. [DOI: 10.1021/acs.jpca.7b11340] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ibrahim Alhroub
- Chemistry Department, Tulane University, New Orleans, Louisiana 70118, United States
| | - Evguenii Kozliak
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Alena Kubátová
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Mark Sulkes
- Chemistry Department, Tulane University, New Orleans, Louisiana 70118, United States
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Apicella B, Wang X, Passaro M, Ciajolo A, Russo C. Accurate calibration of a molecular beam time-of-flight mass spectrometer for on-line analysis of high molecular weight species. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:2183-2190. [PMID: 27479931 DOI: 10.1002/rcm.7702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 07/21/2016] [Accepted: 07/25/2016] [Indexed: 06/06/2023]
Abstract
RATIONALE Time-of-Flight (TOF) Mass Spectrometry is a powerful analytical technique, provided that an accurate calibration by standard molecules in the same m/z range of the analytes is performed. Calibration in a very large m/z range is a difficult task, particularly in studies focusing on the detection of high molecular weight clusters of different molecules or high molecular weight species. METHODS External calibration is the most common procedure used for TOF mass spectrometric analysis in the gas phase and, generally, the only available standards are made up of mixtures of noble gases, covering a small mass range for calibration, up to m/z 136 (higher mass isotope of xenon). In this work, an accurate calibration of a Molecular Beam Time-of Flight Mass Spectrometer (MB-TOFMS) is presented, based on the use of water clusters up to m/z 3000. RESULTS The advantages of calibrating a MB-TOFMS with water clusters for the detection of analytes with masses above those of the traditional calibrants such as noble gases were quantitatively shown by statistical calculations. A comparison of the water cluster and noble gases calibration procedures in attributing the masses to a test mixture extending up to m/z 800 is also reported. In the case of the analysis of combustion products, another important feature of water cluster calibration was shown, that is the possibility of using them as "internal standard" directly formed from the combustion water, under suitable experimental conditions. CONCLUSIONS The water clusters calibration of a MB-TOFMS gives rise to a ten-fold reduction in error compared to the traditional calibration with noble gases. The consequent improvement in mass accuracy in the calibration of a MB-TOFMS has important implications in various fields where detection of high molecular mass species is required. In combustion products analysis, it is also possible to obtain a new calibration spectrum before the acquisition of each spectrum, only modifying some operative conditions. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- B Apicella
- Istituto di Ricerche sulla Combustione, IRC-C.N.R., P.le Tecchio 80, 80125, Napoli, Italy.
| | - X Wang
- SPIN-C.N.R., Via Cintia, 80124, Napoli, Italy
| | - M Passaro
- Istituto di Ricerche sulla Combustione, IRC-C.N.R., P.le Tecchio 80, 80125, Napoli, Italy
| | - A Ciajolo
- Istituto di Ricerche sulla Combustione, IRC-C.N.R., P.le Tecchio 80, 80125, Napoli, Italy
| | - C Russo
- Istituto di Ricerche sulla Combustione, IRC-C.N.R., P.le Tecchio 80, 80125, Napoli, Italy
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Apicella B, Li X, Passaro M, Spinelli N, Wang X. Multiphoton ionization of large water clusters. J Chem Phys 2014; 140:204313. [DOI: 10.1063/1.4878663] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Streibel T, Zimmermann R. Resonance-enhanced multiphoton ionization mass spectrometry (REMPI-MS): applications for process analysis. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2014; 7:361-381. [PMID: 25014345 DOI: 10.1146/annurev-anchem-062012-092648] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Process analysis is an emerging discipline in analytical sciences that poses special requirements on analytical techniques, especially when conducted in an online manner. Mass spectrometric methods seem exceedingly suitable for this task, particularly if a soft ionization method is applied. Resonance-enhanced multiphoton ionization (REMPI) in combination with time-of-flight mass spectrometry (TOFMS) provides a selective and sensitive means for monitoring (poly)aromatic compounds in process flows. The properties of REMPI and various variations of the ionization process are presented. The potential of REMPI for process analysis is highlighted with several examples, and drawbacks of the method are also noted. Applications of REMPI-TOFMS for the detection and monitoring of aromatic species in a large variety of combustion processes comprising flames, vehicle exhaust, and incinerators are discussed. New trends in technical development and combination with other analytical methods are brought forward.
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Affiliation(s)
- Thorsten Streibel
- Joint Mass Spectrometry Centre, Institute of Chemistry, University of Rostock, D-18059 Rostock, Germany;
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Carpentier Y, Pino T, Bréchignac P. R2PI Spectroscopy of Aromatic Molecules Produced in an Ethylene-Rich Flame. J Phys Chem A 2013; 117:10092-104. [PMID: 23865607 DOI: 10.1021/jp400913n] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yvain Carpentier
- Institut des Sciences Moléculaires
d’Orsay, CNRS UMR 8214, Université Paris-Sud, Bât. 210, F-91405 Orsay, France
- Laboratoire de Physique des
Lasers, Atomes et Molécules (PhLAM), UMR CNRS 8523, Centre
d’Études et de Recherches Lasers et Applications, Université de Lille 1, F-59655 Villeneuve d’Ascq
Cedex, France
| | - Thomas Pino
- Institut des Sciences Moléculaires
d’Orsay, CNRS UMR 8214, Université Paris-Sud, Bât. 210, F-91405 Orsay, France
| | - Philippe Bréchignac
- Institut des Sciences Moléculaires
d’Orsay, CNRS UMR 8214, Université Paris-Sud, Bât. 210, F-91405 Orsay, France
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Denifl S, Ptasińska S, Sonnweber B, Scheier P, Liu D, Hagelberg F, Mack J, Scott LT, Märk TD. Free-electron attachment to coronene and corannulene in the gas phase. J Chem Phys 2007; 123:104308. [PMID: 16178598 DOI: 10.1063/1.2008947] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Electron attachment to the polyaromatic hydrocarbons coronene and corannulene is studied in the electron energy range of about 0-14 eV using a high-resolution crossed electron-neutral beam setup. The major anions observed are the parent anions peaking at about 0 eV with cross sections of 3.8 x 10(-20) and 1 x 10(-19) m(2), respectively. The only fragment anions formed in coronene and corannulene are the dehydrogenated coronene and corannulene anions. Other anions observed in the negative mass spectra at about 0 eV can be ascribed to impurities of the sample. High-level quantum-mechanical studies are carried out for the determination of electron affinities, hydrogen binding energies, and structures of both molecules. The behavior of coronene and corannulene upon electron attachment is compared with that of other polyaromatic hydrocarbons studied previously.
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Affiliation(s)
- S Denifl
- Institut für Ionenphysik, Leopold Franzens Universität, Innsbruck, Austria.
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Happold J, Grotheer HH, Aigner M. Distinction of gaseous soot precursor molecules and soot precursor particles through photoionization mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:1247-54. [PMID: 17342787 DOI: 10.1002/rcm.2955] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Samples were drawn from sooting premixed low-pressure ethylene oxygen flames and investigated through photoionization mass spectrometry using either KrF or ArF lasers as the radiation source. With the former, mass spectra were obtained as described in the literature and characterized through a series of signal groups, one for each C-number and extending to about m/z 1000, assigned as a PAH series. When the ArF laser was used the same series was observed with a somewhat higher sensitivity. In addition, a new series was observed overlaid on the PAH series and starting at about m/z 680. The new series exhibited abundant ions and it completely dominated the spectrum beyond m/z 1000. This series was identified as being the spectrum of soot precursor particles. Through measurement of the ionization order it was concluded that at least two photons are needed for ionization of PAHs whereas the particles need only one photon. Consequently, they can be measured with high sensitivity when an ArF laser is used as the radiation source. Furthermore, the discrimination of soot precursor molecules and soot precursor particles becomes possible through photoionization and this enables an improved understanding of the mass spectra. This should allow a particle growth mechanism to be deduced in the near future.
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Affiliation(s)
- Joachim Happold
- German Aerospace Center - Institute of Combustion Technology, Pfaffenwaldring 38-40, Stuttgart 70569, Germany
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Sablier M, Fujii T. 3 Mass spectrometry of free radicals: a methodological overview. ACTA ACUST UNITED AC 2005. [DOI: 10.1039/b408852m] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Deleuze MS. Valence One-Electron and Shake-Up Ionization Bands of Polycyclic Aromatic Hydrocarbons. III. Coronene, 1.2,6.7-Dibenzopyrene, 1.12-Benzoperylene, Anthanthrene. J Phys Chem A 2004. [DOI: 10.1021/jp047224e] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Michael S. Deleuze
- Departement SBG, Limburgs Universitair Centrum, Universitaire Campus, B-3590 Diepenbeek, Belgium
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Maguhn J, Karg E, Kettrup A, Zimmermann R. On-line analysis of the size distribution of fine and ultrafine aerosol particles in flue and stack gas of a municipal waste incineration plant: effects of dynamic process control measures and emission reduction devices. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2003; 37:4761-4770. [PMID: 14594389 DOI: 10.1021/es020227p] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The size distribution of particles in the waste gas of a municipal waste incineration plant (23 MW) was measured on-line at two sampling points in the flue-gas duct (700 and 300 degrees C) as well as in the stack gas (80 degrees C). The measurements were performed during both stable combustion conditions and transient operating conditions. The particle measurements were carried out by a mobile system consisting of a home-designed sampling system with dilution device and a scanning mobility particle sizer (SMPS) for the particle size range 17-600 nm as well as an aerodynamic particle sizer (APS) for the size range 500 nm-30 microm. The APS and SMPS data were combined using a special method and a home written software tool. The maximum of the particle-size distribution in the flue gas of the incinerator shifts from about 90 nm at the 700 degrees C sampling point to about 140 nm at the 300 degrees C point, showing the particle growth by coagulation processes and condensation of inorganic and organic gaseous species with decreasing temperature. This finding is consistent with the measured concentration profiles of gaseous organic chemical species in the flue gas. While at flue-gas temperatures of 600-800 degrees C a rich pattern of polycyclic aromatic hydrocarbon species (PAH) is observable, the PAH concentrations are considerably reduced further downstream of the flue-gas channel, where the temperature drops below 500 degrees C. Condensation and reactive bonding of gaseous chemicals onto particulate matter is, among other reasons, responsible for the depletion of gas-phase species. Process control measures, such as firing the backup burners or cleaning of the grate with pressurized air, can cause dynamic changes of the particle-size distribution. Furthermore the flue-gas cleaning measures have great impact onto both the particle concentration and the size distribution. For this reason the impact of one particular emission reduction device, the wet electrostatic dust precipitator (wet-ESP), is evaluated. The wet-ESP reduces considerably the particle concentration over the whole size range. Behind the flue-gas processing units a broad maximum in the particle-size distribution occurs at about 70 nm, but no pronounced particle-size distribution could be observed. The particle concentration level atthis maximum is about 3 magnitudes lower than in the raw flue gas. However, intermittent periods lasting for several minutes of high emissions of ultrafine particles with d < 40 nm were observed. These particles are most likely formed by nucleation processes behind the wet-ESP from gas-phase constituents of the stack gas.
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Affiliation(s)
- Jürgen Maguhn
- Institut für Okologische Chemie, GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany
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Deleuze MS, Claes L, Kryachko ES, François JP. Benchmark theoretical study of the ionization threshold of benzene and oligoacenes. J Chem Phys 2003. [DOI: 10.1063/1.1589731] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Affiliation(s)
- Michel Sablier
- Département de Chimie, Laboratoire des Mécanismes Réactionnels, UMR 7651 du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex, France
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Schroeter K, Schröder D, Schwarz H. Structures of the C8H6+ Cation Formed upon Loss of Acetylene from Ionized Naphthalene. J Phys Chem A 1999. [DOI: 10.1021/jp990377v] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Katrin Schroeter
- Institut für Organische Chemie der Technischen Universität Berlin, Strasse des 17 Juni 135, D-10623 Berlin, Germany
| | - Detlef Schröder
- Institut für Organische Chemie der Technischen Universität Berlin, Strasse des 17 Juni 135, D-10623 Berlin, Germany
| | - Helmut Schwarz
- Institut für Organische Chemie der Technischen Universität Berlin, Strasse des 17 Juni 135, D-10623 Berlin, Germany
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