Questions tagged [transition-state-theory]
Questions related to explanations of the reaction rates of elementary chemical reactions. The theory assumes a special type of chemical equilibrium (quasi-equilibrium) between reactants and activated transition state complexes.
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Gibbs free energy of transition and activation energy
Let's consider a reaction A (reactant) -> B(product) and activated complex is denoted by C.
This graph ( potential energy vs reaction coordinate ) tells us that reactant need some amount of ...
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rate constant via flux-flux correlation function for linear potential energy surface
How does one calculate fully quantum mechanical rate ($\kappa$) in the golden-rule approximation for two linear potential energy surfaces?
Attempt:
Miller (83) proposes $\kappa=\int{Tr[\exp{(-\beta\...
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Intrinsic Reaction Coordinate - Converting To Reaction Coordinate with Units of Distance
I've located a transition state and ran two IRC calculations (one to get to the product and one to get to the reactant). Is there some type of way of approximating the IRC to something that has units ...
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Understanding transition state theory
Let's say we have standard chemical reaction given by
$$A-B + C \leftrightharpoons [A\cdot\cdot B\cdot\cdot C]^{\dagger} \rightarrow A +B-C$$
I want to estimate the pre-exponential factor of this ...
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Is the minimum energy pathway a geodesic in the potential energy surface?
I just finished NEB-TS calculation using Orca 4.2.1. One of the output file is the minimum energy pathway (MEP) data. Am I correct to interpret the MEP as the geodesic (path of minimum length) on the ...
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Can there be two transition states (first order saddle point) connecting the same pair of minimas on a potential energy surface?
This is a purely hypothetical question. Consider a pair of local minimas A and B on a multi dimensional potential energy surface. Can there be two first saddle points (IE two different configurations) ...
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Why is the transition state the highest energy point? [closed]
If partial bonds form during transition state, it means some energy is released, so how can it have the highest energy? Shouldn't the point before transition state be highest energy? (the point where ...
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Transition State search
I've been trying to find a transition state for the reaction of Pd + F2 with no luck. Has anyone ever tried a similar reaction, have they managed to get the TS? The reaction proceeds from the ...
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Stabilizing donor-acceptor interaction between orthogonal orbitals in the SN2 transition state?
For the $\mathrm{S_N2}$ reaction between chloroacetone and iodide, my professor has drawn a donor-acceptor interaction between the iodine lone pair attacking the Cl-substituted carbon and the π ...
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Investigating the effect of solvents (protic vs aprotic) on the alkaline hydrolysis of ethyl acetate using a conductivity meter
What different areas about solvents can be explored with the conductivities collected of the alkaline hydrolysis of ethyl acetate in propanone and ethanol?
$$\ce{CH3COOC2H5 + NaOH -> CH3COONa + ...
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Intuition of following the lowest curvature mode to find a saddle point on a PES
In this paper A dimer method for finding saddle points on high dimensional potential surfaces using only first derivatives, it is mentioned that
The saddle point is a maximum along the lowest ...
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What is the intuition of using "dimer method" for searching transition states?
I learned dimer method for searching transition state in this paper:
A dimer method for finding saddle points on high dimensional potential surfaces using only first derivatives.
However, I still ...
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Should the normal mode of vibration leading to the transition state be removed?
I would like to know whether the normal mode of vibration of the reactant should be deleted when calculating $\Delta ZPE$ and $\delta G_{\text{corr}}(T)$, where $\Delta ZPE$ is the zero-point energy ...
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Explaining boiling using internal energy
Internal energy is summation of potential and kinetic energies of a substance
Using this interpretation of internal energy, how can I explain boiling?
Kinetic remains constant.
Potential should ...
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Explain the difference between reaction intermediate and reactive intermediate
Wikipedia definitions of the terms:
Reaction intermediate:
https://en.m.wikipedia.org/wiki/Reaction_intermediate
Reactive intermediate:
https://en.m.wikipedia.org/wiki/Reactive_intermediate
What ...
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