Intramolecular reaction rate is not determined exclusively by the distance separating reaction centers. The kinetic consequences of modulated ground state strain on dyotropic hydrogen migration in systems of very similar geometric disposition [Erratum to document cited in CA115(17):182353r]

1991 ◽  
Vol 113 (25) ◽  
pp. 9710-9710
Author(s):  
Leo A. Paquette ◽  
George A. O'Doherty ◽  
Robin D. Rogers
Keyword(s):  
Ground State ◽  
Reaction Rate ◽  
Reaction Centers ◽  
Hydrogen Migration ◽  
Intramolecular Reaction

scholarly journals Influence of resonances on the 11B(n,γ)12B capture reaction rate. Capture to the ground state of 12B

2020 ◽  
Vol 123 ◽  
pp. 102481
Author(s):  
S.B. Dubovichenko ◽  
N.A. Burkova ◽  
A.V. Dzhazairov-Kakhramanov ◽  
A.S. Tkachenko
Keyword(s):  
Ground State ◽  
Reaction Rate ◽  
Capture Reaction

A CNDO/2 Calculation on the Reaction of Ground State Oxygen Atoms with Olefins

1974 ◽  
Vol 52 (2) ◽  
pp. 287-290 ◽  
Author(s):  
Seiichiro Koda
Keyword(s):  
Potential Energy ◽  
Ground State ◽  
Potential Energy Surfaces ◽  
Reaction Rate ◽  
Reaction Intermediates ◽  
Excitation Energies ◽  
Reaction Rate Constants ◽  
Molecular Orbital Study ◽  
Energy Surfaces ◽  
Oxygen Atoms

A molecular orbital study within the framework of the CNDO/2 method has been made of the reactions of ground state oxygen atoms with olefins. Calculated excitation energies confirm the existence of a certain correlation between those and the logarithm of the reaction rate constants. The location of minima in the simplified potential energy surfaces computed appear to correspond to the reaction intermediates suggested previously.

scholarly journals Kinetic Study of the Reaction of Rh(a4F9/2) with N2O, O2 and NO

1998 ◽  
Vol 17 (4) ◽  
pp. 219-237 ◽  
Author(s):  
Mark L. Campbell
Keyword(s):  
Gas Phase ◽  
Excited States ◽  
Ground State ◽  
Rate Constants ◽  
Room Temperature ◽  
Reaction Rate ◽  
Removal Rate ◽  
Reaction Rates ◽  
Bimolecular Reaction ◽  
Temperature Rate

The gas phase reactivity of Rh(a4F9/2) with N2O, O2 and NO is reported. Removal rate constants for the excited states of rhodium below 13,000cm-1 are also reported. The reaction rate of Rh(a4F9/2) with N2O is relatively temperature insensitive. The rate constants for the bimolecular reaction are described in Arrhenius form by (1.3±0.3)×10−12exp⁡(−1.3±0.8KJ/mol/RT)cm3s−1 The reaction rates of the a4F9/2 state with O2 and NO are pressure dependent. For O2, the limiting low-pressure thirdorder, K0, and limiting high-pressure second-order, K∞, room temperature rate constants in argon buffer are (6.6±0.6)×10−30cm6s−1 and (2.1±0.2)×10−11cm3s−1, respectively. For NO, K2 and K∞ are (1.3±0.2×10−30cm6s−1) and (2.1±0.4)×10−11cm3s−1, respectively. The removal rates of the excited states are faster than the ground state by a factor of 2 or more.

scholarly journals Thermodynamic Parameters of the Viscous Flow in the Aqueous Solutions of Polyols

2020 ◽  
Vol 65 (9) ◽  
pp. 810
Author(s):  
O. P. Rudenko ◽  
O. V. Saienko ◽  
R. O. Saienko ◽  
O. S. Svechnikova
Keyword(s):  
Aqueous Solutions ◽  
Viscous Flow ◽  
Reaction Rate ◽  
Bond Formation ◽  
Thermodynamic Characteristics ◽  
Viscous Flows ◽  
Reaction Centers ◽  
Vibration Energy ◽  
Isokinetic Temperature ◽  
Reaction Rate Constants

Data experimentally obtained for the kinematic viscosity are used to calculate the thermodynamic characteristics of viscous flows in some polyols and their aqueous solutions. The solutions of glycerol, erythritol, xylitol, adonite, sorbitol, mannitol, and dulcite are studied, as well as the melts of erythritol, xylitol, and sorbitol. The entropy, enthalpy, and free energy of the viscous flow are calculated in the framework of the theory of reaction rate constants. A linear dependence between the true entropy and the enthalpy of the viscous flow in the researched systems is found, which allowed us to determine the isokinetic temperature, calculate the transmission coefficient, draw a conclusion about the mechanisms of bond formation in the reaction centers of active complexes, and estimate the vibration energy of those bonds.

pH-Dependence, Isotope Effect and Products of Flavin-sensitized Photodecarboxylation and Photodehydrogenation

1972 ◽  
Vol 27 (9) ◽  
pp. 1035-1037 ◽  
Author(s):  
W. Haas ◽  
P. Hemmerich
Keyword(s):  
Isotope Effect ◽  
Ground State ◽  
Reaction Rate ◽  
Ph Dependence ◽  
Rate Of Reaction

The pH-dependence of flavin-sensitized photodehydrogenation and oxidative photodecarboxylation shows a change of reaction rate with an apparent pK of about 5.5. This “photo-pK” cannot be assigned to any known ground state or excited flavin or substrate species, nor is it related to the kind of bond being broken (C-H or C-COO-). Therefore, it is attributed to the pK of a covalent flavin-substrate intermediate. Carboxylates R-COO~ react by decarboxylation, the nature of R determining only the rate of reaction. The acids R -COOH themselves are unreactive, unless functionally substituted at the α-carbon. Hence X-CH(R)-COOH behaves as does X-CH2-R, for X=OH, OR, NH2, NR2. R3N+- CH(R) -COO- is unreactive, while H3N+-CH(R)-COO-is slowly dehydrogenated through its neutral tautomer which is favored in the flavin-substrate exciplex.

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