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标题: How to calculate the Distortion energy ? [打印本页]

作者
Author: vitalys 时间: 2022-2-9 17:10
标题: How to calculate the Distortion energy ?
Hi,Recently, I read the the article titled "Analyzing Reaction Rates with the Distortion/Interaction-Activation Strain Model" DOI : 10.1002/anie.201701486.
What I understood is that it's model to explain reaction rate by performing energy decomposition into two parts , Distortion energy and the interaction energy.
The paper doesn't explain how to compute those two terms of energies. I made my searching in the internet to find out how to determine the Distortion energy, but I can't find a understandable information.
Does Multiwfn support this analysis?

作者
Author: wzkchem5 时间: 2022-2-9 17:34
Didn't the article mention the definition of the distortion energy right above Eq. (5)? "The distortion energy, or activation strain, is defined as the energy required to distort the reactants from their equilibrium geometries to the geometries in the TS." The interaction energy was also defined immediately after this sentence.

作者
Author: flyingchow 时间: 2022-2-10 00:00
If you can read Chinese，the link below will help you a lot.
http://bbs.keinsci.com/thread-23990-1-1.html

作者
Author: vitalys 时间: 2022-2-10 06:54

wzkchem5 发表于 2022-2-9 17:34
Didn't the article mention the definition of the distortion energy right above Eq. (5)? "The distort ...

Dear wzkchem5,
Thank you for your reply, and I did see the definitions, but what I'm searching for is a procedure to start a calculation, a method, what programs I need to use, all the necessary stuff to get start, and how to study a reaction using this model ?

作者
Author: sobereva 时间: 2022-2-10 10:39
There are several utilities dedicated to realize distortion/interaction analysis, see their introduction papers:
J. Comput. Chem., 40, 2227 (2019)
J. Comput. Chem., 40, 2509 (2019)
J. Comput. Chem., 40, 619 (2019)

作者
Author: wzkchem5 时间: 2022-2-10 15:54

vitalys 发表于 2022-2-9 23:54
Dear wzkchem5,
Thank you for your reply, and I did see the definitions, but what I'm searching fo ...

The procedure is already clear from the definition. Once you understand every word of the definition, you can work out the procedure by yourself without any ambiguity. Not all articles give their calculation procedures in a format that can be followed brainlessly, and they do not need to do so in the first place.
Consider the bimolecular reaction of A and B. The TS obviously involves both molecules, but both A and B are distorted at the TS with respect to their optimized geometries. Let's denote the distorted geometries by A' and B'. The distortion energy is then, by definition, the energy required to distort A to A' plus the energy required to distort B to B'. Thus, you (1) optimize the structures of A, B and the TS; (2) cut the TS into the fragments A' and B'; (3) do single point calculations on A' and B' separately; and finally (4) compute the distortion energy from E(A')-E(A)+E(B')-E(B).

作者
Author: vitalys 时间: 2022-2-11 15:06

wzkchem5 发表于 2022-2-10 15:54
The procedure is already clear from the definition. Once you understand every word of the definiti ...

Dear wzkchem5,
Thank you very much.

作者
Author: zako 时间: 2022-2-12 01:27
本帖最后由 zako 于 2022-2-12 01:57 编辑

I think autoDIAS is the best tool to perform such analysis, but when I tried using a simple case like Diels-Alder reaction (Ethylene + Butadiene), I used my IRC output file from Gaussian calculation, the IRC contain 37 points, and when I run autoDIAS I get 111 files to perform single point energy calculations, those 111 files contain input files for each fragment (37 for Ethylene and 37 for Butadiene), and another 37 contain both fragments.
As Mr. wzkchem5 said in his answer, we need only the energies of each fragment, why we need to perform single point energy for both, for example energy of cycloadduct?

作者
Author: wzkchem5 时间: 2022-2-12 02:52

zako 发表于 2022-2-11 18:27
I think autoDIAS is the best tool to perform such analysis, but when I tried using a simple case lik ...

The single point energies of the structures containing both fragments are indeed not needed in the computation of the distortion energy, but are needed in the computation of the interaction energy. Maybe that is the reason?

作者
Author: Julien 时间: 2022-2-25 16:10
本帖最后由 Julien 于 2022-2-25 16:11 编辑

sobereva 发表于 2022-2-10 10:39
There are several utilities dedicated to realize distortion/interaction analysis, see their introduc ...

Dear Professor,
I'm doing a comparison between two reactivity models, the Distortion/Interaction-Activation Strain of Professor Houk, and the Molecular Electron Density Theory (MEDT) of Professor Domingo, I'am confused about which model to use to explain the reactivity, and I confused more when I found a lot of published articles using this models on reputed journals.Recently, I read on Domingo's website (www.luisrdomingo.com), the following paragraph, in which he totally disagree with the model of Professor Houk :

Why Houk's distortion/interaction energy model is an erroneous reactivity model.
  Houk's distortion/interaction [J. Am. Chem. Soc., 2007, 129, 10646] model based on the fragmentation of
  the TS geometry is conceptually erroneous as both molecular energy and geometry depend on the
  electron-density, which physically is not divisible. Since the computed E*distorsion (E*d) is always
  higher than the real one, this model always underestimate the interaction energy E*int, which is the factor
  responsible for the feasibility of an organic reaction.

How true the explanation of Professor Domingo in the precedent paragraph ? and, which reactivity model is the most reliable to explain the reactivity ?
Is there some points that support one model against the other, or they are both complementary to each other ?

The most important question, on what base should I choose model to explain the reactivity of my reactions ?

Best regards

作者
Author: wzkchem5 时间: 2022-2-25 19:23
本帖最后由 wzkchem5 于 2022-2-25 12:29 编辑

Julien 发表于 2022-2-25 09:10
Dear Professor,
I'm doing a comparison between two reactivity models, the Distortion/Interaction- ...

The concept "reactivity" is not rigorously defined in the first place. As a consequence it's not at all surprising that different people may insist on using different methods to quantify reactivity. You can choose to be with any camp as long as your analyses are internally consistent.

作者
Author: Julien 时间: 2022-2-25 20:28

wzkchem5 发表于 2022-2-25 19:23
The concept "reactivity" is not rigorously defined in the first place. As a consequence it's not a ...

Thank you wzkchem5 for your prompt reply, but it's not a matter of being with a camp or favour one against the other, it's about the most logical and reliable, for example, the above paragraph in red give a strong indications that the Houk's model is wrong and trusted, that's why I posted my questions in this forum, to verify the Domingo's statement. Is the Houk's model can be used or should be rejected ?

作者
Author: sobereva 时间: 2022-2-25 21:57

Julien 发表于 2022-2-25 16:10
Dear Professor,
I'm doing a comparison between two reactivity models, the Distortion/Interaction- ...

Distortion/interaction analysis is obviously not rigorous, as there must be coupling between geometry distortion and change in interaction. However, it doesn't mean this analysis is completely useless, some physical insights can more or less be revealed by it if you correctly understand its idea and limitation.

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