Photodissociation of HN3in the Vacuum‐Ultraviolet Production and Reactivity of Electronically Excited NH

1968 ◽  
Vol 49 (6) ◽  
pp. 2726-2733 ◽  
Author(s):  
Hideo Okabe
Keyword(s):  
Vacuum Ultraviolet ◽  
Electronically Excited

Photochemistry of acetylene

1983 ◽  
Vol 61 (5) ◽  
pp. 850-855 ◽  
Author(s):  
H. Okabe
Keyword(s):  
Quantum Yield ◽  
Ground State ◽  
Vacuum Ultraviolet ◽  
Inert Gases ◽  
Primary Process ◽  
Fluorescence Studies ◽  
Ethynyl Radical ◽  
Absorption Of Light ◽  
Electronically Excited

Photochemical and fluorescence studies of acetylene initiated by absorption of light in the vacuum ultraviolet have been described. The photochemical primary process consists of (1) the formation of C2 + H2, (2) the production of C2H + H, and (3) the formation of a metastable acetylene. The quantum yield of process (1) is about 0.1 and that of process (2) is 0.06 at 1849 Å and 0.3 at 1470 Å. The metastable acetylene either reacts with ground state acetylene to produce diacetylene or is deactivated by collisions with the walls, inert gases, or by fluorescence. A quasicontinuous emission is observed in the 4000 to 6000 Å region when acetylene is exposed to incident wavelengths below 1305 Å. This emission is ascribed to an electronically excited ethynyl radical. The rates of reaction C2H + H2 → C2H2 + H and C2H + RH → C2H2 + R (RH = CH4, C2H6, C3H8) have been measured. The photochemistry of acetylene in the Jovian and Titan atmospheres is briefly discussed.

Studies of the First Electronically Excited State of 3-Fluoropyridine and its Ionic Structure by Means of REMPI, Two-Photon MATI, One-Photon VUV-MATI Spectroscopy and Franck-Condon Analysis

2021 ◽  
Author(s):  
Niklas Helle ◽  
Tim Raeker ◽  
Jürgen Grotemeyer
Keyword(s):  
Vacuum Ultraviolet ◽  
Ionic Structure ◽  
Two Photon ◽  
Electronically Excited State ◽  
Electronically Excited ◽  
Photon Ionization ◽  
Mati Spectroscopy ◽  
Franck Condon ◽  
Photon Resonance

3-Fluoropyridine (3-FP) has been investigated by means of two-photon resonance-enhanced multi photon ionization (REMPI), mass-analyzed threshold ionization (MATI) and one-photon vacuum-ultraviolet (VUV) MATI spectroscopy. The aim was the determination of...

scholarly journals Comprehensive investigation of the electronic excitation of W(CO)6 by photoabsorption and theoretical analysis in the energy region from 3.9 to 10.8 eV

2017 ◽  
Vol 8 ◽  
pp. 2208-2218 ◽  
Author(s):  
Mónica Mendes ◽  
Khrystyna Regeta ◽  
Filipe Ferreira da Silva ◽  
Nykola C Jones ◽  
Søren Vrønning Hoffmann ◽  
...  
Keyword(s):  
Electron Scattering ◽  
Cross Sections ◽  
Lower Energy ◽  
Density Functional ◽  
Vacuum Ultraviolet ◽  
Energy Bands ◽  
Ligand Charge Transfer ◽  
Comprehensive Knowledge ◽  
Relativistic Time ◽  
Electronically Excited

High-resolution vacuum ultraviolet photoabsorption measurements in the wavelength range of 115–320 nm (10.8–3.9 eV) have been performed together with comprehensive relativistic time-dependent density functional calculations (TDDFT) on the low-lying excited sates of tungsten hexacarbonyl, W(CO)6. The higher resolution obtained reveals previously unresolved spectral features of W(CO)6. The spectrum shows two higher-energy bands (in the energy ranges of 7.22–8.12 eV and 8.15–9.05 eV), one of them with clear vibrational structure, and a few lower-energy shoulders in addition to a couple of lower-energy metal-to-ligand charge-transfer (MLCT) bands reported in the literature before. Absolute photoabsorption cross sections are reported and, where possible, compared to previously published results. On the basis of this combined experimental/theoretical study the absorption spectrum of the complex has been totally re-assigned between 3.9 and 10.8 eV under the light of spin–orbit coupling (SOC) effects. The present comprehensive knowledge of the nature of the electronically excited states may be of relevance to estimate neutral dissociation cross sections of W(CO)6, a precursor molecule in focused electron beam induced deposition (FEBID) processes, from electron scattering measurements.

The Vacuum Ultraviolet Photolysis of Cyclopentanone

1972 ◽  
Vol 50 (24) ◽  
pp. 3938-3943 ◽  
Author(s):  
Alfred A. Scala ◽  
Daniel G. Ballan
Keyword(s):  
Quantum Yield ◽  
Carbonyl Group ◽  
Incident Energy ◽  
Vacuum Ultraviolet ◽  
Quantum Yields ◽  
Electronically Excited ◽  
Ultraviolet Photolysis

In the vacuum ultraviolet photolysis of cyclopentanone, the major modes of fragmentation of the electronically excited ketone are:[Formula: see text]The sum of the quantum yields for reactions A and B is 0.87 at 147.0 nm and these reactions become less important as the incident energy is increased. A pressure study at 147.0 nm of the partitioning of the tetramethylene diradical between paths A and B indicates that the ratio kA/kB is approximately 8. The quantum yield for reaction 8 is only 0.02. The remainder of the decomposition of cyclopentanone is accounted for by reactions 4 and 5, which appear to become more significant as the incident energy increases. The mechanisms for reactions 6 and 8 are best interpreted in terms of diradicals of structure (CH2)n where n = 1, 3, and 4. The lack of non-acyl σ-cleavage at 147.0 nm is an indication that the absorption of energy occurs at the carbonyl group.

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