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Identification of the fragment of the 1-methylpyrene cation by mid-IR spectroscopy.

ABSTRACT: The fragment of the 1-methylpyrene cation, C17H11+, is expected to exist in two isomeric forms, 1-pyrenemethylium PyrCH2+ and the tropylium containing species PyrC7+. We measured the infrared (IR) action spectrum of cold C17H11+ tagged with Ne using a cryogenic ion trap instrument coupled to the FELIX laser. Comparison of the experimental data with density functional theory calculations allows us to identify the PyrCH2+ isomer in our experiments. The IR Multi-Photon Dissociation spectrum was also recorded following the C2H2 loss channel. Its analysis suggests combined effects of anharmonicity and isomerisation while heating the trapped ions, as shown by molecular dynamics simulations.

SUBMITTER: Jusko P

PROVIDER: S-EPMC5988045 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Identification of the fragment of the 1-methylpyrene cation by mid-IR spectroscopy.

Jusko Pavol P Simon Aude A Wenzel Gabi G Brünken Sandra S Schlemmer Stephan S Joblin Christine C

Chemical physics letters 20180401

The fragment of the 1-methylpyrene cation, C17H11+, is expected to exist in two isomeric forms, 1-pyrenemethylium PyrCH2+ and the tropylium containing species PyrC7+. We measured the infrared (IR) action spectrum of cold C17H11+ tagged with Ne using a cryogenic ion trap instrument coupled to the FELIX laser. Comparison of the experimental data with density functional theory calculations allows us to identify the PyrCH2+ isomer in our experiments. The IR Multi-Photon Dissociation spectrum was als ...[more]

PMID: 29882538

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Identification of the fragment of the 1-methylpyrene cation by mid-IR spectroscopy.

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Identification of the fragment of the 1-methylpyrene cation by mid-IR spectroscopy.

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