Spectroscopic Characterization and Photochemistry of the Vinylsulfinyl Radical

Author(s):  
Zhuang Wu ◽  
Lina Wang ◽  
Bo Lu ◽  
André K. Eckhardt ◽  
Peter Richard Schreiner ◽  
...  

The simplest α,β-unsaturated sulfinyl radical CH2=C(H)SO• has been generated in the gas phase by high-vacuum flash pyrolysis (HVFP) of sulfoxide CH2=C(H)S(O)CF3 at ca. 800 °C. Two planar cis and trans...

2021 ◽  
Author(s):  
Bifeng Zhu ◽  
Zhuang Wu ◽  
Lina Wang ◽  
Tarek Trabelsi ◽  
Joseph S. Francisco ◽  
...  

By high-vacuum flash pyrolysis of bis(trifluoromethyl)disulfane oxide (CF3S(O)SCF3) at 400 °C, the elusive trifluoromethylthiyl radical (CF3S•) has been efficiently generated in the gas phase. Subsequent isolation of CF3S• in cryogenic...


1981 ◽  
Vol 46 (2) ◽  
pp. 340-353
Author(s):  
Pavel Zachař ◽  
Zdeněk Bastl ◽  
Jakub Adámek

Chemisorption of ethylene was studied on thin polycrystalline layers of nickel prepared by metal deposition in high vacuum and modified by preadsorbed oxygen. The volumetric method combined with the gas-phase analysis and the measurement of the electrical resistance changes of these layers were used. Already small amounts of preadsorbed oxygen of the order of 10-2 of the monolayer affect rather substantially the extent of ethylene chemisorption. The extent of the initial irreversible chemisorption and also the total adsorption of ethylene as a function of the amount of preadsorbed oxygen have a maximum at the surface oxygen concentration of 3 . 1013 molecule cm-2. The adsorption accompanied by the extensive dissociation of ethylene C-H bonds proceeds predominantly on nickel atoms with lower coordination (atoms on the microcrystal edges, corner atoms, etc.), where also oxygen chemisorption proceeds preferentially.


2021 ◽  
Vol 23 (11) ◽  
pp. 6462-6471
Author(s):  
Piyush Mishra ◽  
Sean M. Fritz ◽  
Sven Herbers ◽  
Alexander M. Mebel ◽  
Timothy S. Zwier

The flash pyrolysis of trans 3-pentenenitrile was studied by mass-correlated broadband microwave spectroscopy, where both molecular and radical species were observed within our jet-cooled molecular beam, including 2,4-pentadienenitrile.


2021 ◽  
Author(s):  
Ettore Fois ◽  
Mario Oriani ◽  
gloria tabacchi

Octyl methoxycinnamate (OMC) is a commercial sunscreen with excellent UVB filter properties. However, it is known to undergo a series of photodegradation processes that decrease its effectiveness as UVB filter. In particular, the trans (E) form - which is considered so far the most stable isomer - converts to the cis (Z) form under the effect of light. In this work, by using post-Hartree-Fock approaches (CCSD, CCSD(t) and CCSD+T(CCSD)) on ground state OMC geometries optimized at the MP2 level we show that the cis and trans form of the gas-phase OMC molecule have comparable stability. Our results suggest that the cis form is stabilized by intra-molecular dispersion interactions, leading to a folded, more compact structure than the trans isomer.<br>


2016 ◽  
Vol 13 (4) ◽  
pp. 770-781 ◽  
Author(s):  
Baghdad Science Journal

New series of metal ions complexes have been prepared from the new ligand 1,5- Dimethyl-4- (5-oxohexan-2- ylideneamino) -2-phenyl- 1H-pyrazol-3 (2H)-one derived from 2,5-hexandione and 4-aminophenazone. Then, its V(IV), Ni(II), Cu(II), Pd(II), Re(V) and Pt(IV) complexes prepared. The compounds have been characterized by FT-IR, UV-Vis, mass and 1H and 13C-NMR spectra, TGA curve, magnetic moment, elemental microanalyses (C.H.N.O.), chloride containing, Atomic absorption and molar conductance. Hyper Chem-8 program has been used to predict structural geometries of compounds in gas phase, the heat of formation, (binding, total and electronic energy) and dipole moment at 298 K.


2018 ◽  
Vol 71 (5) ◽  
pp. 348 ◽  
Author(s):  
Hossein Shirani ◽  
Hassan Sabzyan

Electric dipole moments, polarizabilities, and IR, Raman, optical rotatory dispersion, and electronic and vibrational circular dichroism spectra of the four cis–trans isomers of the proposed [(CO)2(benzoate)FeII/III(terephthalate)CoIII/II(benzoate)(CO)2]+ binuclear complex, having bistablity due to intramolecular charge transfer (IMCT), is investigated using the time-dependent density functional theory ((TD)DFT) B3LYP/6–31G(d,p)[LanL2DZ] method. Results show that the two FeII–CoIII and FeIII–CoII IMCT states of this binuclear complex have distinctly different spectroscopic, optical, and electric response properties, and are sensitive to the cis–trans arrangement of the ligands around the two metallic centres. Furthermore, intrinsic reaction coordinates inter-connecting the two IMCT states are identified using the Duschinsky matrix method. Only one or two of the normal coordinates remain almost (above 80 %) intact during the IMCT reaction which denotes global changes in the bonding strengths and potential energy hypersurface of this bistable binuclear complex. Analysis of the calculated spin densities characterizes the IMCT transition state structures of the trans–trans, cis–cis, and trans–cis isomers as early, early, and late transition states, respectively.


1984 ◽  
Vol 38 ◽  
Author(s):  
Joda C. Wormhoudt ◽  
Alan C. Stanton ◽  
Joel A. Silver

AbstractTwo processes of great importance in the semiconductor industry are vapor deposition and plasma etching. This paper presents a review of laser techniques for spectroscopic characterization of the gas phase species involved in these processes. Band strength and other spectroscopic data for selected molecules are used to give estimates of the detection sensitivity in vibrational and electronic bands. Preliminary results are given from work presently in progress in our laboratory on the detection of such species. The discussion includes examples of the application of these techniques to a number of laboratory deposition and etching devices.


1976 ◽  
Vol 7 (24) ◽  
pp. no-no
Author(s):  
CARY W. BLUME ◽  
I. C. HISATSUNE ◽  
JULIAN HEICKLEN
Keyword(s):  

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