Multiwfn forum

alessiomacorano

Member

Registered: 2023-12-19

Posts: 8

Polar surface area

Dear Prof Tian Lu 

I would like to ask you one question about the topological surface analysis from .fchk of Gaussian or related QM software, the .fchk are generated from chk with b3lyp/6-311++g(d,p) with SMD implicit model solvent water.

On some drug like molecules i would like to use PSA (polar surface area) as molecular descriptors.

To do this i tried to calculate with multiwfn software from .fchk of Gaussian 16 software, but I obtain different values of PSA respect to Pubchem for example, and I don't understand why.

Maybe the difference is for the implicit model solvent ? should i have to consider in gas phase ?

Thank you so much for your work and this forum

Alessio

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 2,011

Website

Re: Polar surface area

Dear Alessio,

Please note that there is no unique definition of molecular surface and its polar subregion. In main function 12, by default the isosurface of rho=0.001 a.u. is used to define vdW surface, in which the subregion with |ESP|>10 kcal/mol is regarded as polar part. This definition must be different to the so-called topological polar surface area in your screenshot.

Best regards,

Tian

alessiomacorano

Member

Registered: 2023-12-19

Posts: 8

Re: Polar surface area

Dear Prof Tian Lu, probably I think that the different value from Multiwfn and pubchem are different because from pubchem the polar surface area is calculated with Cactvus software (which probably, I'm checking in the meantime) used the topological polar surface area defined by Peter ERTL in his paper.

Probably this can take into account for the difference.

Regarding to the Polar surface area from MULTIWFN do you have more reference apart the manual, I ask you for the ongoing publication.

Thank you so much !!

Alessio Macorano

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 2,011

Website

Re: Polar surface area

Dear Alessio Macorano,

I am sure that when I have spare time, I will publish the definition of polar surface area.

Best,

Tian