All Questions
Tagged with transition-state-theory physical-chemistry
8
questions
2
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0
answers
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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 ...
3
votes
0
answers
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Is standard change in activation Gibbs free energy indepedent of pressure?
For a chemical reaction the activation volume is defined as:
$$Δ^{\ddagger}V={V^\ddagger}-V$$
where both $V^\ddagger$ and $V$ refer to standard states (I have omitted the symbol for simplicity). One ...
4
votes
2
answers
387
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Why only molecules with three or more atoms undergo unimolecular reaction?
Only molecules with three or more atoms undergo unimolecular reactions. A diatomic molecule cannot dissociate in this way because it has a single mode of vibrational freedom. If this mode is excited ...
2
votes
0
answers
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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\...
1
vote
1
answer
534
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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 ...
7
votes
2
answers
433
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Transition state - multidimensional surfaces
I've been reading an explanation about transition states in Smith's Organic Synthesis:
A transition state is an energy maximum along the reaction coordinate. However, a chemical
reaction where ...
14
votes
1
answer
3k
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Why are the total energies of transition states so commonly corrected for zero-point vibrational energy?
So often I see total energies of transition states corrected for zero-point vibrational energy which always confuses me. Zero point energy is the lowest energy that a ground state minimum energy ...
14
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3
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Transition state and free energy
We have products $\ce{A + B}$ combining to form $\ce{C + D}$ through the transition state $\ce{X}$.
Are all reactions at least virtually reversible? Is the difference between a reversible reaction ...