Identification of spectra of mixed structural isomers via mass selective hole-burning in the gas phase

1992 ◽  
Vol 195 (1) ◽  
pp. 11-15 ◽  
Author(s):  
W. Scherzer ◽  
H.L. Selzle ◽  
E.W. Schlag
Keyword(s):  
Gas Phase ◽  
Hole Burning ◽  
Structural Isomers

Structural Isomers of the Benzene Dimer from Mass Selective Hole-Burning Spectroscopy

1992 ◽  
Vol 47 (12) ◽  
pp. 1248-1252 ◽  
Author(s):  
W. Scherzer ◽  
O. Krätzschmar ◽  
H. L. Selzle ◽  
E. W. Schlag
Keyword(s):  
Gas Phase ◽  
Ground State ◽  
Supersonic Jet ◽  
Hole Burning ◽  
Structural Isomers ◽  
Benzene Dimer ◽  
Supersonic Jet Expansion

Mass selected hole-burning experiments in the gas phase are presented for the benzene dimer formed in a supersonic jet expansion. The observed spectra show three different ground state configurations for the dimer. From isotopically substituted dimers the structure of the most prominent conformer could be assigned to a very floppy T-shape like structure with two non-equivalent sites for the benzene molecules.

scholarly journals Structural isomers and low-lying electronic states of gas-phase M+(N2O)n (M = Co, Rh, Ir) ion–molecule complexes

2019 ◽  
Vol 21 (26) ◽  
pp. 13959-13967 ◽  
Author(s):  
Ethan M. Cunningham ◽  
Alexander S. Gentleman ◽  
Peter W. Beardsmore ◽  
Stuart R. Mackenzie
Keyword(s):  
Density Functional Theory ◽  
Nitrous Oxide ◽  
Gas Phase ◽  
Density Functional ◽  
Electronic States ◽  
Structural Isomers ◽  
Functional Theory ◽  
Phase Group ◽  
Ion Molecule Complexes ◽  
Metal Ligand

The structures of gas-phase group nine cation–nitrous oxide metal–ligand complexes, M+(N2O)n (M = Co, Rh, Ir; n = 2–7) have been determined by a combination of infrared photodissociation spectroscopy and density functional theory.

Gas Phase Ionization of Toluene: Benzylium Versus Tropylium Pathway

2019 ◽  
Vol 9 (2) ◽  
pp. 138-150
Author(s):  
Thao Nguyen ◽  
Mario Aparicio ◽  
Mahmoud A. Saleh
Keyword(s):  
Gas Phase ◽  
Radical Cation ◽  
Collision Energy ◽  
New Technologies ◽  
Accurate Mass ◽  
Gas Chromatography Mass Spectrometry ◽  
Hydrogen Atoms ◽  
Structural Isomers ◽  
Acetylene Molecule ◽  
High Resolution Gas Chromatography

Aim: In this investigation, we used accurate mass high-resolution gas chromatography mass spectrometry to study the gas phase carbocations rearrangements and fragmentation of toluene and halo-toluenes as well as their deuterium labeled compounds. Objective: Accurate mass of selected ions from ionization of toluene and related compounds revealed that the initially formed radical cation C7H8 +. does not rearrange to tropylium radical cation contradicting published literature. Methods: When the toluene radical cation was purely selected, it was found to lose a free radical (hydrogen atom) at collision energies greater than 5 eV and forming benzylium or tropylium cation C7H7 + (m/z = 91), with no other fragmentations. Results: The resulting cation at collision energy greater than 20 eV fragmented by losing acetylene or ethylene or allene molecule to form C5H5 + (m/z = 65), C5H3 + (m/z = 63) or C4H3 + (m/z = 51) respectively. Purely selected C5H5 + cation at collision energy greater than 30 eV lost acetylene molecule and formed C3H3 + (m/z =39). Conclusion: In this investigation toluene, halotoluene and their deuterated derivatives (structural isomers) were found to ionize in the gas phase with isomer retention. Historically, it has been suggested that the seven carbons and hydrogen atoms would become indistinguishable. However, this should be revised in the light of new technologies.

scholarly journals Gas-phase synthesis of benzene via the propargyl radical self-reaction

2021 ◽  
Vol 7 (21) ◽  
pp. eabf0360
Author(s):  
Long Zhao ◽  
Wenchao Lu ◽  
Musahid Ahmed ◽  
Marsel V. Zagidullin ◽  
Valeriy N. Azyazov ◽  
...  
Keyword(s):  
Gas Phase ◽  
Aromatic Hydrocarbons ◽  
Theoretical Calculations ◽  
Branching Ratios ◽  
Structural Isomers ◽  
Phase Synthesis ◽  
Solar Systems ◽  
Propargyl Radical ◽  
Polycyclic Aromatic ◽  
Hydrocarbon Chemistry

Polycyclic aromatic hydrocarbons (PAHs) have been invoked in fundamental molecular mass growth processes in our galaxy. We provide compelling evidence of the formation of the very first ringed aromatic and building block of PAHs—benzene—via the self-recombination of two resonantly stabilized propargyl (C3H3) radicals in dilute environments using isomer-selective synchrotron-based mass spectrometry coupled to theoretical calculations. Along with benzene, three other structural isomers (1,5-hexadiyne, fulvene, and 2-ethynyl-1,3-butadiene) and o-benzyne are detected, and their branching ratios are quantified experimentally and verified with the aid of computational fluid dynamics and kinetic simulations. These results uncover molecular growth pathways not only in interstellar, circumstellar, and solar systems environments but also in combustion systems, which help us gain a better understanding of the hydrocarbon chemistry of our universe.

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