Iodine-Catalyzed Isomerization ofn-Heptenes. Thermodynamic Data for the Positional and Geometrical Isomerization and thecisEffect in the Entropy Difference of Geometrical Isomer Pairs

1967 ◽  
Vol 89 (3) ◽  
pp. 504-509 ◽  
Author(s):  
Kurt W. Egger
Keyword(s):  
Thermodynamic Data ◽  
Geometrical Isomer ◽  
Geometrical Isomerization

One-Way Geometrical Isomerization of 1,1-Diarylethenes Induced by Photosensitized Electron Transfer

2003 ◽  
Vol 17 (08n09) ◽  
pp. 1492-1497
Author(s):  
Yasuhiko Kawamura ◽  
Takaaki Ishiduka ◽  
Masao Tsukayama
Keyword(s):  
Electron Transfer ◽  
Molecular Oxygen ◽  
Radical Cation ◽  
Decomposition Product ◽  
Geometrical Isomer ◽  
Geometrical Isomerization ◽  
Butyl Group ◽  
Distonic Radical Cation ◽  
E And Z Isomers ◽  
Molecular Framework

One-way geometrical isomerization around a C=C bond of 1,1-diary1-2-t-butylethene is achieved upon photoirradiation of cyanoaromatics as a light-absorbing sensitizer. In the thermochemical view, there is no difference between both E and Z isomers of the ethene. Key intermediate is a putative distonic radical cation which is a unique one having a spatially separate radical and ionic centers on the molecular framework. Generation of such an intermediate is due to the presence of a π-donating substituent on an aromatic ring and a bulky t-butyl group. Molecular oxygen interacts as superoxide with the C=C bond of the radical cation in a [supra + antara] manner to give a decomposition product, i.e. a benzophenone derivative and pivalaldehyde, via a dioxetane and competitively, one geometrical isomer of the ethene is afforded by splitting oxygen before making two bonds with the ethene radical cation and superoxide.

Adsorption and corrosion inhibition characteristics of two medicinal molecules

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Hydrochloric Acid ◽  
Corrosion Rate ◽  
Mild Steel ◽  
Corrosion Inhibition ◽  
Half Life ◽  
Thermodynamic Data ◽  
Inhibition Efficiency ◽  
Gravimetric Method ◽  
Corrosive Environment ◽  
Corrosion Inhibition Efficiency

The corrosion inhibition characteristics of two medicinal molecules phenylalanine and rutin on mild steel in 1.0M Hydrochloric acid were evaluated using gravimetric method. Corrosion inhibition efficiency of 83.78 and 90.40 % was obtained respectively after seven days. However, phenylalanine showed weak accumulative higher corrosion inhibition efficiency. The presence of both molecules in the corrosive environment reduced the corrosion rate constant and increased the material half-life. Thermodynamic data calculated suggests a spontaneous adsorption of the molecules on the mild steel’s surface.

The Potential-pH Diagrams Depicting the Hydrogen Chemisorption in the Pt-H2O, Ir-H2O, and Rh-H2O Systems at 25 °C

1995 ◽  
Vol 60 (4) ◽  
pp. 553-558 ◽  
Author(s):  
Tomáš Loučka
Keyword(s):  
Thermodynamic Data ◽  
Hydrogen Chemisorption

Thermodynamic data for the chemisorption of hydrogen on the Pt, Ir, and Rh electrodes were evaluated from data in the literature. On the basis of these data, the potential-pH diagrams were calculated for the Pt-H2O, Ir-H2O, and Rh-H2O systems describing the hydrogen chemisorption. For the hydrogen chemisorption, the surface was considered to be uniformly inhomogeneous.

Thermodynamic Data of Iodine Reactions Calculated by Quantum Chemistry. Training Set of Molecules

2008 ◽  
Vol 73 (10) ◽  
pp. 1340-1356 ◽  
Author(s):  
Katarína Mečiarová ◽  
Laurent Cantrel ◽  
Ivan Černušák
Keyword(s):  
Quantum Chemistry ◽  
Ab Initio ◽  
Thermodynamic Data ◽  
Theoretical Calculations ◽  
Reactor Core ◽  
Fission Products ◽  
Vapour Phase ◽  
Reactor Accident ◽  
Training Set ◽  
Coolant System

This paper focuses on the reactivity of iodine which is the most critical radioactive contaminant with potential short-term radiological consequences to the environment. The radiological risk assessments of 131I volatile fission products rely on studies of the vapour-phase chemical reactions proceeding in the reactor coolant system (RCS), whose function is transferring the energy from the reactor core to a secondary pressurised water line via the steam generator. Iodine is a fission product of major importance in any reactor accident because numerous volatile iodine species exist under reactor containment conditions. In this work, the comparison of the thermodynamic data obtained from the experimental measurements and theoretical calculations (approaching "chemical accuracy") is presented. Ab initio quantum chemistry methods, combined with a standard statistical-thermodynamical treatment and followed by inclusion of small energetic corrections (approximating full configuration interaction and spin-orbit effects) are used to calculate the spectroscopic and thermodynamic properties of molecules containing atoms H, O and I. The set of molecules and reactions serves as a benchmark for future studies. The results for this training set are compared with reference values coming from an established thermodynamic database. The computed results are promising enough to go on performing ab initio calculations in order to predict thermo-kinetic parameters of other reactions involving iodine-containing species.

Modelling the thermodynamic data for hcp Zn and Cu–Zn alloys– an ab initio and calphad approach

Calphad ◽  
2021 ◽  
Vol 72 ◽  
pp. 102253
Author(s):  
Alan Dinsdale ◽  
Alexandra Khvan ◽  
Ekaterina A. Smirnova ◽  
Alena V. Ponomareva ◽  
Igor A. Abrikosov
Keyword(s):  
Ab Initio ◽  
Thermodynamic Data ◽  
Calphad Approach ◽  
Zn Alloys
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