Multiwfn forum / Multiwfn and wavefunction analysis

Electron Density with various q

dummy@example.com (sobereva) — Wed, 29 Apr 2026 01:33:04 +0000

Hello,

There is no so-called "extra point charge" in this context. Electron density is calculated directly based on wavefunction according to the equation given in Section 2.6 of Multiwfn manual.

Polarizability of a molecule in the excited state

dummy@example.com (Danmed) — Tue, 28 Apr 2026 10:32:03 +0000

That's right, thank you so much and sorry for the confussion.

Issues with Hirshfeld-I charge calculation

dummy@example.com (sobereva) — Thu, 23 Apr 2026 01:58:47 +0000

1 l1.exe is an executable file of Gaussian package, it is indispensible when running Gaussian. Because GAUSS_EXEDIR environment variable was not defined, l1.exe cannot be found. The current issue comes from the fact that Gaussian was not properly installed on the machine actually used for Gaussian calculation.

2 You used a wrong input file. The input file for any wavefunction analysis must contain wavefunction information. For Gaussian users, .fch/fchk, .wfn and .wfx file can be used. Please check Section 2.5 of Multiwfn to gain basic knowledge about input file of Multiwfn.

deformation density analysis

dummy@example.com (sobereva) — Tue, 14 Apr 2026 22:08:26 +0000

Dear Thangavel,

Yes, some Multiwfn users have similar feedback. But implementation of sobEDA utilizes some special features of Gaussian, which may not be easily realized in ORCA and I don't have enough time to dive into it. However, if anyone is able to successfully create an ORCA-based sobEDA.sh script, it would be great and I definitively will promote it.

Best regards,

Tian

Intramolecular sobEDA analysis

dummy@example.com (sobereva) — Fri, 10 Apr 2026 22:21:22 +0000

This will more or less introduce some artificial factors; however, by properly constructing the model dimer system, the artifical effect can be minimzed to a negligible extent. For example, one may need to perform constraint optimization to avoid occurrence of evident steric repulsion between the two fragments in the originally bonded region...

Discrepancy in Hirshfeld charges between ORCA 6.1 output and Multiwfn

dummy@example.com (sobereva) — Fri, 27 Mar 2026 21:25:24 +0000

ealanis wrote:

sobereva wrote:
atmraddens.f90 file can be found in the source code package of Multiwfn, in this file you can find "subroutine genatmradpos", which defines radial density for all elements. After replacing the existing data of Tb by the data in sphavgval.txt, you need to recompile Multiwfn to make the modification take effect.

Thank you, I really appreciate the guidance. The Ln complexes are trivalent though. Do I need to generate the reference densities in this Oxidation state, i.e. as Ln(III)? Or in the neutral ground state configuration.

must in the neutral ground state configuration, according to the definition of Hirshfeld method

How to export 3D grid data (not just visualization) in Multiwfn?

dummy@example.com (sobereva) — Wed, 25 Mar 2026 21:12:20 +0000

Hello,

You can use main function 5 of Multiwfn to calculate grid data for a real space function, then in the post-processing menu, you can choose to export the grid data as the very popular .cub file. See Section 4.5 of Multiwfn manual for examples.

NTOs from "plain text input"

dummy@example.com (Marlen) — Wed, 25 Mar 2026 12:15:29 +0000

Dear Professor Lu,

thank you very much for your answer again!

Best regards,
Roman

How to visualize ESP derived from multiwfn 3.7 in VMD2

dummy@example.com (CompChem2025) — Wed, 25 Mar 2026 05:46:58 +0000

Thank you Sir!

Calculating the Exciton Couplings using TrESP

dummy@example.com (sobereva) — Fri, 20 Mar 2026 01:06:23 +0000

The steps are seemingly correct.

Please note that when calculating the monomers in Gaussian, "nosymm" keyword should be used to prevent Gaussian from automatically reorientating the system coordinate, otherwise the coordinates of the monomers will finally overlap with each other, and thus the calculated exciton coupling will be completely wrong.

Energy implementation of the ETS-NOCV analysis

dummy@example.com (sobereva) — Thu, 19 Mar 2026 00:23:38 +0000

It's true. The effect of this approximation is usually negligible.
If you want to obtain exact total orbital interaction energy, it is suggested to use sobEDA method (J. Phys. Chem. A 2023, 127, 7023−7035). The sum of all NOCV pair contributions may be scaled to the exact value to derive slightly more accurate contribution of each NOCV pair.

The composition of NOCV pairs

dummy@example.com (shtajner) — Tue, 17 Mar 2026 10:25:12 +0000

Thank you very much!

How to plot plane map for IRI without covalent bond regions?

dummy@example.com (sobereva) — Fri, 06 Mar 2026 17:22:36 +0000

Hello,

There is no corresponding option in the post-processing menu of main function 4. You can simply use main function 4 to plot RDG instead of IRI.

Electron density difference plot - help!

dummy@example.com (meurglys) — Fri, 06 Mar 2026 13:36:06 +0000

Dear Tian Lu,

I am a new user of Multiwfn (3.8 dev), first I would like to thank you a lot for this amazing software!

At the moment I am interested in charge transfer phenomena. I would like to reproduce the example on amino-nitro-biphenyl molecule (P2) as described in section 4.18.3 of Multwfn manual in order to generate a nice electron density difference plot (as seen for instance in Theor Chem Acc 2016, 135, 173), but I am not sure about what I am doing as I could not reproduce your results. This is what I am doing (I use Gaussian 16).

1) Optimization of P2 in the ground state: #p opt freq PBE1PBE/6-31+g(d) scrf=(iefpcm,solvent=ethanol)
2) Single-point TDDFT on the optimized ground state geometry: #p td=(root=1,singlet) PBE1PBE/6-31+g(d) scrf=(iefpcm,solvent=ethanol)

then I convert chk files to fch, and then fch to wfn using multiwfn. After following the steps on p.798-799 of the manual, my results are very off.

So could you please tell me what I am doing wrong here? I don't have to optimize the geometry in the excited state as the two geometries must be identical, right? Additionnaly I have a few questions:

a) Why did you use the keyword "density" in the extP2.gjf file?
b) I tried the procedure with .fch files instead of .wfn files and did not see any difference. Are .wfn files needed in this instance?

Thanks a lot in advance for taking the time to answer and have great day!

Cheers,

Meurglys

Problem with Calculating oxidation state using LOBA method

dummy@example.com (Ameland) — Fri, 06 Mar 2026 10:01:29 +0000

Thanks a lot, I downloaded the latest version and it works.