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How do we calculate local electrophilicity or nucleophilicity...
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+ Computational chemistry
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Michael Jacobs
How do we calculate local electrophilicity or nucleophilicity...
The fukui function can be used to extract the property of electrophilicity and nucleophilicity. In DFT calculation, you can also extract those properties using IP and EA value. I think you need to read J. Am. Chem. Soc. 1999, 121, 1922-1924 paper.
The fukui function can be used to extract the property of electrophilicity and nucleophilicity. In DFT calculation, you can also extract those properties using IP and EA value. I think you need to read J. Am. Chem. Soc. 1999, 121, 1922-1924 paper.
With the optimized neutral molecular structure at hand, one has to compute the atomic spin density of the radical anion and of the radical cation of the neutral molecule geometry at the same computational level (i.e. single point calculation at UB3LYP/6-31G(d)/charge -1/multiplicity 2 for radical anion and UB3LYP/6-31G(d)/charge +1/multiplicity 2; note that open-shell formalism must be used since they are doublet radicals). In the output of both open-shell calculations, one has to find the Mulliken atomic charges or Natural ones if a NBO calculation has been performed (their results tend to be very similar between them) and collect them separately. Then, we are ready to compute the electrophilic Parr functions from the radical anion atomic charges and the nucleophilic Parr functions from the radical cation ones. You may use this link for further insight: https://www.dropbox.com/s/uy5cn29poyd6dvp/tut-2-Parr-v1-en.pdf?dl=0
With the optimized neutral molecular structure at hand, one has to compute the atomic spin density of the radical anion and of the radical cation of the neutral molecule geometry at the same computational level (i.e. single point calculation at UB3LYP/6-31G(d)/charge -1/multiplicity 2 for radical anion and UB3LYP/6-31G(d)/charge +1/multiplicity 2; note that open-shell formalism must be used since they are doublet radicals). In the output of both open-shell calculations, one has to find the Mulliken atomic charges or Natural ones if a NBO calculation has been performed (their results tend to be very similar between them) and collect them separately. Then, we are ready to compute the electrophilic Parr functions from the radical anion atomic charges and the nucleophilic Parr functions from the radical cation ones. You may use this link for further insight: https://www.dropbox.com/s/uy5cn29poyd6dvp/tut-2-Parr-v1-en.pdf?dl=0
All you can get by calculating Fukui Indices. Fukui indices are, in short, reactivity indices; they give us information about which atoms in a molecule have a larger tendency to either loose or accept an electron, which we chemist interpret as which are more prone to undergo a nucleophilic or an electrophilic attack, respectively. This in turn has to do with a molecule’s tendency of becoming polarized in the presence of an external field or upon the change of electron density. The key word here is electron density, the whole idea behind Fukui’s lies in the realm of conceptual DFT. for more details...see this blog http://joaquinbarroso.com/2010/07/26/how-to-calculate-fukui-indices/
All you can get by calculating Fukui Indices. Fukui indices are, in short, reactivity indices; they give us information about which atoms in a molecule have a larger tendency to either loose or accept an electron, which we chemist interpret as which are more prone to undergo a nucleophilic or an electrophilic attack, respectively. This in turn has to do with a molecule’s tendency of becoming polarized in the presence of an external field or upon the change of electron density. The key word here is electron density, the whole idea behind Fukui’s lies in the realm of conceptual DFT. for more details...see this blog http://joaquinbarroso.com/2010/07/26/how-to-calculate-fukui-indices/
The local electrophilicity (ωk) [1] oncentrated on atom k was calculated by projecting the index ω onto any reaction center k in the molecule using the Parr function f+k:
ω k= f+k*ω.
The local nucleophilicity (Nk) 25 concentrated on atom k was calculated using the global nucleophilicity N and the Parr function P−k according to the formula:
The local electrophilicity (ωk) [1] oncentrated on atom k was calculated by projecting the index ω onto any reaction center k in the molecule using the Parr function f+k:
ω k= f+k*ω.
The local nucleophilicity (Nk) 25 concentrated on atom k was calculated using the global nucleophilicity N and the Parr function P−k according to the formula:
The fukui function can be used to extract the property of electrophilicity and nucleophilicity. In DFT calculation, you can also extract those properties using IP and EA value. I think you need to read J. Am. Chem. Soc. 1999, 121, 1922-1924
paper.
The fukui function can be used to extract the property of electrophilicity and nucleophilicity. In DFT calculation, you can also extract those properties using IP and EA value. I think you need to read J. Am. Chem. Soc. 1999, 121, 1922-1924
paper.
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With the optimized neutral molecular structure at hand, one has to compute the atomic spin density of the radical anion and of the radical cation of the neutral molecule geometry at the same computational level (i.e. single point calculation at UB3LYP/6-31G(d)/charge -1/multiplicity 2 for radical anion and UB3LYP/6-31G(d)/charge +1/multiplicity 2; note that open-shell formalism must be used since they are doublet radicals). In the output of both open-shell calculations, one has to find the Mulliken atomic charges or Natural ones if a NBO calculation has been performed (their results tend to be very similar between them) and collect them separately. Then, we are ready to compute the electrophilic Parr functions from the radical anion atomic charges and the nucleophilic Parr functions from the radical cation ones.
You may use this link for further insight:
https://www.dropbox.com/s/uy5cn29poyd6dvp/tut-2-Parr-v1-en.pdf?dl=0
With the optimized neutral molecular structure at hand, one has to compute the atomic spin density of the radical anion and of the radical cation of the neutral molecule geometry at the same computational level (i.e. single point calculation at UB3LYP/6-31G(d)/charge -1/multiplicity 2 for radical anion and UB3LYP/6-31G(d)/charge +1/multiplicity 2; note that open-shell formalism must be used since they are doublet radicals). In the output of both open-shell calculations, one has to find the Mulliken atomic charges or Natural ones if a NBO calculation has been performed (their results tend to be very similar between them) and collect them separately. Then, we are ready to compute the electrophilic Parr functions from the radical anion atomic charges and the nucleophilic Parr functions from the radical cation ones.
You may use this link for further insight:
https://www.dropbox.com/s/uy5cn29poyd6dvp/tut-2-Parr-v1-en.pdf?dl=0
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All you can get by calculating Fukui Indices.
Fukui indices are, in short, reactivity indices; they give us information about which atoms in a molecule have a larger tendency to either loose or accept an electron, which we chemist interpret as which are more prone to undergo a nucleophilic or an electrophilic attack, respectively. This in turn has to do with a molecule’s tendency of becoming polarized in the presence of an external field or upon the change of electron density. The key word here is electron density, the whole idea behind Fukui’s lies in the realm of conceptual DFT.
for more details...see this blog
http://joaquinbarroso.com/2010/07/26/how-to-calculate-fukui-indices/
All you can get by calculating Fukui Indices.
Fukui indices are, in short, reactivity indices; they give us information about which atoms in a molecule have a larger tendency to either loose or accept an electron, which we chemist interpret as which are more prone to undergo a nucleophilic or an electrophilic attack, respectively. This in turn has to do with a molecule’s tendency of becoming polarized in the presence of an external field or upon the change of electron density. The key word here is electron density, the whole idea behind Fukui’s lies in the realm of conceptual DFT.
for more details...see this blog
http://joaquinbarroso.com/2010/07/26/how-to-calculate-fukui-indices/
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Thank you
Thank you
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The local electrophilicity (ωk) [1] oncentrated on atom k was calculated by projecting the index ω onto any reaction center k in the molecule using the Parr function f+k:
- ω k= f+k*ω.
The local nucleophilicity (Nk) 25 concentrated on atom k was calculated using the global nucleophilicity N and the Parr function P−k according to the formula:[1] Domingo LR, Perez P, Saez JA (2013 RSC Adv 3:1486–1494
The local electrophilicity (ωk) [1] oncentrated on atom k was calculated by projecting the index ω onto any reaction center k in the molecule using the Parr function f+k:
- ω k= f+k*ω.
The local nucleophilicity (Nk) 25 concentrated on atom k was calculated using the global nucleophilicity N and the Parr function P−k according to the formula:[1] Domingo LR, Perez P, Saez JA (2013 RSC Adv 3:1486–1494
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Ernest Opoku Do you have other directives for step by step approach to calculate radical electrophilicity index (local)?
Ernest Opoku Do you have other directives for step by step approach to calculate radical electrophilicity index (local)?
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