Multiwfn forum
Multiwfn official website: http://sobereva.com/multiwfn. Multiwfn forum in Chinese: http://bbs.keinsci.com/wfn
You are not logged in.
- Topics: Active | Unanswered
Pages: 1
#1 Multiwfn and wavefunction analysis » Extracting ESP Along a Line » 2025-05-21 05:05:29
- Ainosya
- Replies: 1
Hello,
I have a CI system for which I would like to obtain the electrostatic potential (ESP) along a line.
More precisely, I want to plot the ESP along a line approaching my system with a charge of -1.
Is there a way to do this using Multiwfn?
My guess is that I need to generate several .fchk files at various distances using Gaussian, but it's still unclear to me how to extract the ESP value, since Multiwfn typically plots the isosurface directly.
Thank you
#2 Re: Multiwfn and wavefunction analysis » Discrepancy in Electronic Spatial Extent Between Multiwfn and Gaussian » 2025-05-17 17:21:55
After compiling source code, directly copying settings.ini from binary package to source code folder (or where you want to put Multiwfn).
Oh, okay.
I wouldn’t have expected to need to do that, since it means I have to download both somehow.
Thanks!
#3 Re: Multiwfn and wavefunction analysis » Discrepancy in Electronic Spatial Extent Between Multiwfn and Gaussian » 2025-05-17 17:20:31
By the way, there is discrepancy between the output given by isuerfunc
And the one returns by doing Multiwfn → 300 → 5 
The difference is not significant, but ideally, there should be no difference at all.
#4 Re: Multiwfn and wavefunction analysis » Discrepancy in Electronic Spatial Extent Between Multiwfn and Gaussian » 2025-05-17 17:10:50
I guess my previous messages were unclear. I have version 3.8 and decided to switch to the source code package.
In doing so, I realized that neither the source code nor the settings.ini file needs to be modified, since this feature is already available in the code—although it's not mentioned in the manual for some reason.
However, since there is no settings.ini file in the source code package, I would like to know how to configure the user-defined functions in case I need to adjust them later
#5 Re: Multiwfn and wavefunction analysis » Discrepancy in Electronic Spatial Extent Between Multiwfn and Gaussian » 2025-05-17 16:19:07
I just realized that there's no need to modify the settings.ini file (which I could not find in the source code btw).
Launching Multiwfn → 300 → 5 returns the electronic spatial extent.
For some reason, this feature isn't mentioned in the manual — or did I miss it?
I discovered this while digging through the source code
#6 Re: Multiwfn and wavefunction analysis » Discrepancy in Electronic Spatial Extent Between Multiwfn and Gaussian » 2025-05-17 16:15:13
Okay, this is strange — I noticed that even though I set iuserfunc = 3, it still remains at 0.
So, I decided to use the development version instead of the binary one. However, I couldn't find where the value of iuserfunc is defined in the code. There is no settings.ini file when compiling the code directly.
Can you please tell me wehre the c80tmp (I guess) is defined so I can directly recompile the code. Thanks!
#7 Multiwfn and wavefunction analysis » Discrepancy in Electronic Spatial Extent Between Multiwfn and Gaussian » 2025-05-14 16:12:58
- Ainosya
- Replies: 8
Hello,
I am trying to obtain the electronic spatial extent using different software. To do so, I modified the settings.ini file in Multiwfn by setting iuserfunc = 3.
Multiwfn returns a value of 21092.4988259881, whereas my g16.log output gives 18436.6750. Is there a specific reason that could explain such a discrepancy?
I am unable to upload my files to the forum due to their large size, but could you please confirm whether my procedure for obtaining ⟨R²⟩ using Multiwfn is correct, or if I might be doing something wrong?
Thank you
Pages: 1