Multiwfn forum

taha55

Member

Registered: 2019-09-19

Posts: 37

ESP map Fukui functions

Hello Professsor Tian Lu

Which of the following(1 or 2) is true that relationship between the red and blue regions of the MEP map and the fukui functions?

1. Red colour areas: electronically rich→nucleophile (proton-loving)→nucleophilic attack→f+ (fukui) values are positive and high
Blue colour areas: electronically poor→electrophile (electron-loving)→electrophilic attack→f- (fukui) values are positive and high

Or

2. Red colour areas: electronically rich→nucleophile (proton-loving)→electrophilic attack→f- (fukui) values are positive and high
Blue colour areas: electronically poor→electrophile (electron-loving)→nucleophilic attack→f+ (fukui) values are positive and high

Best Regards

Last edited by taha55 (2020-04-05 09:18:31)

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,773

Website

Re: ESP map Fukui functions

Please note there is no direct relationship between distribution of ESP and Fukui function. A site with more negative ESP on its local vdW surface doesn't necessarily mean it must have more positive f-, the analysis results of the two methods sometimes contradict with each other.

As for your figure, this statement is approximately correct:
Red colour areas: negative ESP → electronically rich → nucleophile (proton-loving) → easily undergo electrophilic attack (i.e. electrophilic reagents tend to interact with this site)

taha55

Member

Registered: 2019-09-19

Posts: 37

Re: ESP map Fukui functions

Professsor Tian Lu, thank you very much

I ask this question independently of ESP. Many articles are described differently.

So,is the following conclusion correct for Fukui functions?

F+→ easily undergo nukleophilic attack (i.e. nukleophilic reagents tend to interact with this site)
F-→ easily undergo electrophilic attack (i.e. electrophilic reagents tend to interact with this site)

Last edited by taha55 (2020-04-05 11:47:24)

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,773

Website

Re: ESP map Fukui functions

Yes, you are right

taha55

Member

Registered: 2019-09-19

Posts: 37

Re: ESP map Fukui functions

Professsor Tian Lu, thank you very much
Best Regard