Multiwfn forum / surface charge density

Re: surface charge density

dummy@example.com (saeed_E) — Wed, 06 Aug 2025 18:50:00 +0000

Thank you.

Re: surface charge density

dummy@example.com (sobereva) — Wed, 06 Aug 2025 18:45:42 +0000

As I noted earlier, this depends on how the surface is defined. If it is defined as isosurface of electron density, then "a" will be a constant for all atoms and all molecules, making the discussion completely meaningless.

Re: surface charge density

dummy@example.com (saeed_E) — Wed, 06 Aug 2025 18:26:35 +0000

Thanks a lot.
Could you please make your meaning more evident?
For example, it is said that the surface charge density of atoms X in compound XY is "a" e/squar Angstrom. How is the value of "a" determined?

Saeed

Re: surface charge density

dummy@example.com (sobereva) — Wed, 06 Aug 2025 15:12:18 +0000

"amount of electric charge per unit surface area" is not well-defined. If one uses isosurface of electron density to define the surface, then electron density is the same everywhere on the surface. Statistics information of ESP over the surface is more meaningful and well-defined.

surface charge density

dummy@example.com (saeed_E) — Wed, 06 Aug 2025 12:49:52 +0000

Dear Tian,
Hi, I hope you are doing well.
Suppose I want to determine the surface charge density for the sodium atom in a compound like NaOH. In other words, I’d like to calculate the amount of electric charge per unit surface area on the sodium atom. Could you please let me know how this can be achieved using Multiwfn in a clear and step-by-step explanation?

Sincerely yours,
Saeed