F 1s spectroscopy and ionic fragmentation of trifluoropropyne

2008 ◽  
Vol 86 (8) ◽  
pp. 761-768
Author(s):  
John J Neville ◽  
Narayana P Appathurai ◽  
Yongheng Fan ◽  
Samuel Odoh ◽  
Liu Yang
Keyword(s):  
Rydberg States ◽  
Branching Ratios ◽  
Shape Resonance ◽  
The Core ◽  
Flight Mass Spectrometry ◽  
Exchange Approximation ◽  
Ionic Fragmentation ◽  
Singly Charged ◽  
Fluorinated Carbon ◽  
Overlapping Bands

The F 1s excitation spectroscopy and ionic fragmentation of 3,3,3-trifluoro-1-propyne have been studied using synchrotron radiation and ion time-of-flight mass spectrometry. The total ion yield spectrum and photoionization branching ratios in the vicinity of the F 1s ionization threshold are reported. Core excited state calculations using the static exchange approximation are used to aid in the interpretation of the experimental results. The F 1s excitation spectrum consists of a number of broad overlapping bands below threshold, attributed to excitations to mixed σ*(C-F)/π*(C-C) molecular orbitals and unresolved Rydberg states, and a continuum shape resonance 12.5 eV above threshold. Ionic fragmentation following F 1s excitation or ionization results overwhelmingly in singly charged ionic fragments, primarily via cleavage of bonds to the fluorinated carbon atom adjacent to the core-excited atom.Key words: F 1s excitation, XANES, photoelectron-photoion coincidence, ionic fragmentation, static exchange approximation.

COLLISION INDUCED FRAGMENTATION OF FULLERENE CLUSTERS (C60)n

2005 ◽  
Vol 19 (15n17) ◽  
pp. 2345-2352 ◽  
Author(s):  
B. MANIL ◽  
P. BODUCH ◽  
A. CASSIMI ◽  
O. KAMALOU ◽  
L. MAUNOURY ◽  
...  
Keyword(s):  
Collision Energy ◽  
Thermal Dissociation ◽  
Carbon Clusters ◽  
Size Distributions ◽  
Charge Mobility ◽  
Flight Mass Spectrometry ◽  
Singly Charged ◽  
Doubly Charged ◽  
Fullerene Clusters ◽  
Large Charge

Clusters of C 60 fullerenes are (multi)-ionised in collisions with O 5+ projectiles at a collision energy of 100 keV. The dominant fragmentation channels are analysed by time-of-flight mass spectrometry for different cluster size distributions. Singly charged [Formula: see text], ions are found to be the dominant fragments, in 25% connected with the loss of one or more C 2-units. This result is explained by the large charge mobility in fullerene clusters. Doubly charged fragments, in form of [Formula: see text] and [Formula: see text], contribute to the observed spectrum with less than 5–10% only and are mainly attributed to the fragmentation of dimers. Singly charged small carbon clusters in the size range n = 7 to 19 are formed with low kinetic energies indicating the importance of thermal dissociation processes. The present experiments confirm earlier conclusions on the charge mobility in fullerene clusters.

Branching ratios for autoionisation of ν=3 Rydberg states in nitric oxide

1986 ◽  
Vol 19 (23) ◽  
pp. 3909-3917 ◽  
Author(s):  
J Kimman ◽  
J W J Verschuur ◽  
M Lavollee ◽  
H B van Linden van de Heuvell ◽  
M J van der Wiel
Keyword(s):  
Nitric Oxide ◽  
Rydberg States ◽  
Branching Ratios

Energy levels, Auger branching ratios, and radiative rates of the core-excited states of B-like carbon

2011 ◽  
Vol 135 (12) ◽  
pp. 124309 ◽  
Author(s):  
Yan Sun ◽  
Feng Chen ◽  
Bing Cong Gou
Keyword(s):  
Excited States ◽  
Energy Levels ◽  
Branching Ratios ◽  
The Core

scholarly journals Ultrafast Relaxation Dynamics of the S1 (nπ*) State and the 3p and 3d Rydberg States in Cyclohexanone by Femtosecond Photoelectron Imaging

2019 ◽  
Author(s):  
Ole Hüter ◽  
Niklas Helle ◽  
Friedrich Temps
Keyword(s):  
Imaging Spectroscopy ◽  
Rydberg States ◽  
Population Transfer ◽  
Relaxation Dynamics ◽  
Photoelectron Imaging ◽  
Time Resolved ◽  
Flight Mass Spectrometry ◽  
Vibronic Interactions ◽  
Photon Excitation ◽  
Photoelectron Imaging Spectroscopy

<div>The radiationless decay dynamics of the S1 (nπ*) state and the 3p and 3d Rydberg states of cyclohexanone are investigated using femtosecond time-resolved time-of- flight mass spectrometry and photoelectron imaging spectroscopy. After two-photon excitation of the 3p and 3d states, an ultrafast population transfer to the 3s state is observed within < 120 fs. We ascribe this behavior to strong vibronic interactions of the excited Rydberg states with the <sup>1</sup>ππ* valence state that enable an ultrafast population transfer via an avoided crossing and the subsequent passage of a conical intersection between the respective electronic states. Eventually, the 3s state deactivates by internal conversion to the S<sub>1</sub> (nπ*) state, which in turn is found to be long-lived with a decay time of ~ 300 - 800 ps.</div>

scholarly journals Ionic Fragmentation of NO Following Excitation of the NK-Shell and the OK-Shell Electron

1995 ◽  
Vol 16 (1) ◽  
pp. 5-18 ◽  
Author(s):  
Isao H. Suzuki ◽  
Norio Saito
Keyword(s):  
Kinetic Energy ◽  
Time Of Flight ◽  
Molecular Ion ◽  
Fragment Ions ◽  
Simulation Calculation ◽  
Measured Time ◽  
Ionic Fragmentation ◽  
Singly Charged ◽  
Doubly Charged ◽  
X Ray Absorption

Ionic fragmentation of NO stimulated by soft X-ray absorption has been studied using a monochromatized synchrotron radiation and a time-of-flight mass spectrometer. In photoexcitation of a 1s electron, the singly charged molecular ion NO+ was formed only at 410 and 533 eV (transitions to the 2π orbital), and a fragment ion N+ had the highest intensity in all the energies. The doubly charged molecular ion was produced appreciably, and fragment ions (N2+ and O2+) were formed considerably even below the 1s ionization thresholds. The measured time-of-flight spectra were converted into kinetic energy distributions of N+, O+, N2+ and O2+ at photon energies for characteristic excitation by a simulation calculation. The dissociation pathways from the core-hole states of NO were discussed using the kinetic energy distribution and ion intensity ratios as well as Auger electron spectra in the literature.

Resonance measurements of d-f-g-h intervals in Rydberg states of sodium and a redetermination of the core polarizabilities

1988 ◽  
Vol 38 (10) ◽  
pp. 4985-4993 ◽  
Author(s):  
L. G. Gray ◽  
X. Sun ◽  
K. B. MacAdam
Keyword(s):  
Rydberg States ◽  
The Core

scholarly journals Characterization of Saponins from Various Parts of Platycodon grandiflorum Using UPLC-QToF/MS

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 107
Author(s):  
So-Jeong Lee ◽  
Heon-Woong Kim ◽  
Suji Lee ◽  
Ryeong Ha Kwon ◽  
Hyemin Na ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Total Content ◽  
Dry Weight ◽  
Acid Group ◽  
Ultra Performance Liquid Chromatography ◽  
Human Consumption ◽  
Platycodon Grandiflorum ◽  
The Core ◽  
Flight Mass Spectrometry

Platycodon grandiflorum (PG) is known as a high-potential material in terms of its biological activity. The objective of this report is to provide chromatographic and mass fragment ion data of 38 simultaneously identified saponins, including novel compounds, by analyzing them through ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QToF/MS). In so doing, we investigated their diverse conditions, including morphological parts (stems, roots, buds, and leaves), peeling (or not), and blanching of PG. The total contents of individual saponins indicated an order of roots (containing peel, 1674.60 mg/100 g, dry weight) > buds (1364.05) > roots (without peel, 1058.83) ≈ blanched roots (without peel, 945.17) ≈ stems (993.71) ≈ leaves (881.16). When considering three types of aglycone, the platycodigenin group (55.04 ~ 68.34%) accounted for the largest proportion of the total content, whereas the platycogenic acid A group accounted for 17.83 ~ 22.61%, and the polygalacic acid group represented 12.06 ~ 22.35%. As they are classified as major compounds, novel saponins might be utilized for their role in healthy food for human consumption. Additionally, during blanching, the core temperature of PG was satisfied with the optimal condition, thus activating the enzymes related to biotransformation. Furthermore, through the use of this comprehensive data, additional studies related to buds, as well as roots or the characterization of individual saponins, can be conducted in a rapid and achievable manner.

Broad shape resonance effects in CaF Rydberg states

2006 ◽  
Vol 124 (19) ◽  
pp. 194302 ◽  
Author(s):  
Serhan N. Altunata ◽  
Stephen L. Coy ◽  
Robert W. Field
Keyword(s):  
Rydberg States ◽  
Shape Resonance ◽  
Resonance Effects

Second-order polarization energies for Rydberg states

1992 ◽  
Vol 70 (2-3) ◽  
pp. 187-190 ◽  
Author(s):  
R. A. Swainson ◽  
G. W. F. Drake
Keyword(s):  
Rydberg State ◽  
Rydberg States ◽  
Second Order ◽  
Multipole Moments ◽  
The Core ◽  
Variational Calculations ◽  
Analytic Expressions ◽  
Level Shifts ◽  
Experimental Transition ◽  
Asymptotic Potential

The energy level shifts for an electron in a high-nL Rydberg state of an atom such as helium are well described by an asymptotic potential with terms proportional to the multipole moments of the core. We obtain exact analytic expressions as a function of n and L for second-order perturbation corrections to the energy due to the asymptotic potential. The results are of importance in the analysis of high-precision variational calculations and experimental transition energies for Rydberg states.

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