The internal energy of sputtered glycerol molecules, determined by photoionization mass spectrometry

1988 ◽  
Vol 88 (9) ◽  
pp. 5314-5322 ◽  
Author(s):  
R. Hoogerbrugge ◽  
M. Bobeldijk ◽  
P. G. Kistemaker ◽  
J. Los
Keyword(s):  
Mass Spectrometry ◽  
Internal Energy ◽  
Photoionization Mass Spectrometry

scholarly journals Ab initio dynamics and photoionization mass spectrometry reveal ion–molecule pathways from ionized acetylene clusters to benzene cation

2017 ◽  
Vol 114 (21) ◽  
pp. E4125-E4133 ◽  
Author(s):  
Tamar Stein ◽  
Biswajit Bandyopadhyay ◽  
Tyler P. Troy ◽  
Yigang Fang ◽  
Oleg Kostko ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Ab Initio ◽  
Internal Energy ◽  
Aromatic Ring ◽  
Growth Mechanism ◽  
Product Distribution ◽  
Ab Initio Molecular Dynamics ◽  
Unimolecular Decomposition ◽  
Photoionization Mass Spectrometry ◽  
Excess Internal Energy

The growth mechanism of hydrocarbons in ionizing environments, such as the interstellar medium (ISM), and some combustion conditions remains incompletely understood. Ab initio molecular dynamics (AIMD) simulations and molecular beam vacuum-UV (VUV) photoionization mass spectrometry experiments were performed to understand the ion–molecule growth mechanism of small acetylene clusters (up to hexamers). A dramatic dependence of product distribution on the ionization conditions is demonstrated experimentally and understood from simulations. The products change from reactive fragmentation products in a higher temperature, higher density gas regime toward a very cold collision-free cluster regime that is dominated by products whose empirical formula is (C2H2)n+, just like ionized acetylene clusters. The fragmentation products result from reactive ion–molecule collisions in a comparatively higher pressure and temperature regime followed by unimolecular decomposition. The isolated ionized clusters display rich dynamics that contain bonded C4H4+ and C6H6+ structures solvated with one or more neutral acetylene molecules. Such species contain large amounts (>2 eV) of excess internal energy. The role of the solvent acetylene molecules is to affect the barrier crossing dynamics in the potential energy surface (PES) between (C2H2)n+ isomers and provide evaporative cooling to dissipate the excess internal energy and stabilize products including the aromatic ring of the benzene cation. Formation of the benzene cation is demonstrated in AIMD simulations of acetylene clusters with n > 3, as well as other metastable C6H6+ isomers. These results suggest a path for aromatic ring formation in cold acetylene-rich environments such as parts of the ISM.

Understanding the Homogeneous Reactions of Primary Tar from Biomass Pyrolysis by Means of Photoionization Mass Spectrometry

2020 ◽  
Vol 34 (10) ◽  
pp. 12678-12687 ◽  
Author(s):  
Ke Yang ◽  
Jiahao Wang ◽  
Jiahui Huang ◽  
Jiuzhong Yang ◽  
Yang Pan ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Biomass Pyrolysis ◽  
Photoionization Mass Spectrometry ◽  
Homogeneous Reactions

Analysis of neonicotinoids from plant material by desorption atmospheric pressure photoionization-mass spectrometry

2015 ◽  
Vol 29 (5) ◽  
pp. 424-430 ◽  
Author(s):  
Anu Vaikkinen ◽  
Henning S. Schmidt ◽  
Iiro Kiiski ◽  
Sari Rämö ◽  
Kati Hakala ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Atmospheric Pressure ◽  
Plant Material ◽  
Atmospheric Pressure Photoionization ◽  
Photoionization Mass Spectrometry

Thermochemistry of Organic and Heteroorganic Species. Part IX. Photoionization Studies of Isomerization and Fragmentation of Polysubstituted Cyclopropenes: Phenyl-Substituted Cyclopropenes

2000 ◽  
Vol 6 (1) ◽  
pp. 53-64 ◽  
Author(s):  
V.V. Takhistov ◽  
I.N. Domnin ◽  
D.A. Ponomarev
Keyword(s):  
Mass Spectrometry ◽  
Enthalpy Of Formation ◽  
Good Alternative ◽  
Enthalpies Of Formation ◽  
Isodesmic Reactions ◽  
Ion Structure ◽  
Photoionization Mass Spectrometry ◽  
General Methodology ◽  
Fragment Ions ◽  
The Enthalpy Of Formation

Ionization and appearance energies of some fragment ions from 1,2,3-trimethy1-3-phenyl-, 3-methyl-1,2,3-triphenyl-, 1,2-diphenyl-3-methoxycarbonyl-, 1,2,3-triphenyl-3-methoxycarbonyl- and 1,3,3-triphenyl-2-methoxycarbonyl-cyclopropenes were measured by photoionization mass spectrometry. It was shown that in none of these compounds did the fragment ions possess the expected stable substituted cyclopropenium ion structure. Accordingly, possible schemes of molecular ion isomerization are given. The enthalpies of formation of nearly 50 substituted cyclopropenium ions, and ions of related structure, were estimated using series of isodesmic reactions. This publication, together with the previous works of the authors in this Journal, demonstrates the general methodology for estimation of the enthalpy of formation for even-electron ions. It is suggested that the present methodology can provide a good alternative to other estimation or computation procedures applied to the thermochemistry of ions.

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