Multiwfn forum

There is no existing function for this purpose. Manually calculating it is easy: Using Multiwfn to simulate spectrum, export the two curves as text files,  import them into e.g. Origin, define a new column as their overlap, then perform numerical integration.

I prefer to display all surface extrema, but only manually label some of them, namely the relative important ones (i.e. the ones with relative large magnitude of ESP)

Dear Alessio,

"(full,mbs,hirshfeld" in fact is redundant.

Multiwfn is unable to print bond order in the exactly same way as NBO, but you can use Multiwfn to calculate Mayer bond order, which is very close to the bond order given by NBO when diffuse functions are not employed. When diffuse functions are needed, you can use Multiwfn to calculate fuzzy bond order, which is quite insensitive to basis set and the result is also quite close to the bond order given by NBO. Introduction to Mayer and fuzzy bond orders can be found in Section 3.11 of Multiwfn manual, and relevant examples are given in Section 4.9.1 of Multiwfn manual.

Best,

Tian

In principle, the larger the ngen, the higher the proability to find the most stable configuration, but evidently, the higher the computational cost, which is linearly proportional to ngen.

Please upload figure(s) to describe the issues you encounted. You raised many questions, but without figures, I can hardly understand your problems and difficulties.

BTW: In the recent Multiwfn introduction paper J. Chem. Phys., 161, 082503 (2024) DOI: 10.1063/5.0216272, Fig. 14 is a very representative ESP colored vdW surface map, I think the graphical effect is good enough.

Dear Saeed,

Yes, it can be easily realized via Molclus. Generally, using genmer (a tool in molclus package) to generate a batch of initial guessing complex structures, and then use molclus to invoke quantum chemistry codes to automatically calculate them (geometry optimization + high-level single point calculation) and then sort the resulting energies via isostat. Examples are given in http://bbs.keinsci.com/thread-2369-1-1.html

Best regards,

Tian

New update on 2025-Jun-3:

The aforementioned improvement has also been available for Linux version! Note that for Linux version, before dragging the system to change viewpoint, one should click drawing region once to make icon become a hand.

Around nuclear positions of very heavy atoms, the fluctuation range of Laplacian of rho is extremely large, so the automatically determined Y-axis range is also extremely wide. In order to clearly view the function variation in the bonding region, you should properly adjust range of Y-axis. For example, -100 to 100 a.u.

Please send me your input file of quantum chemistry program and wavefunction file to my E-mail, I will try to reproduce your result.

Please upload a screenshot of option 0 of topology analysis module, to graphically show current CPs and bond paths. If CP index is correct and corresponding bond paths have already been generated by Multiwfn, there is no reason the curve map cannot be plotted. Section "4.2.3 Plot real space function along bond path" of Multiwfn manual has described full steps of generating this kind of map.

In the topology analysis module of Multiwfn, after entering option "-5 Modify or print detail or export paths, or plot property along a path" and then "7 Calculate and plot specific real space function along a path", you will find the following prompt:

 Input index of a path, e.g. 3     Input "q" can return
 Hint: If input index of two paths (e.g. 6,7) emitted from the same (3,-1) CP, then the real space function along the combined paths will be outputted
 Hint: If you input e.g. c6 and meantime the CP6 is BCP, then the two bond paths emitted from it will be chosen

As indicated by the prompt, to plot a complete bond path (linking two atoms and passing through a BCP), it is suggested to input e.g. c6, where 6 is an index of BCP, you will obtain the complete path passing through BCP 6.

You just need one wavefunction file. After loading it into Multiwfn, you can easily use main function 3 to plot ESP along a specific line. See Section 4.3 of Multiwfn manual for examples of using main function 3.

To delete it in Multiwfn, in the topology analysis interface, choose " -5 Modify or print detail or export paths, or plot property along a path", and then "3 Delete some paths", then follow the prompts to input.

You can also choose to show/hidden some topology paths in VMD. In the paths.pdb exported by Multiwfn, you can find different paths correpond to different residue index. So, in VMD, you can enter "Graphics" - "Representation", and in "Selected Molecule" select the ID used to showing paths, then if you input e.g. "not resid 3" in the "Selected Atoms" box, then the 3rd path will be invisible.

Deleting H-H bond path is often acceptable, as it usually only implies an extremely weak interaction (except for case of dihydrogen bond, which is a relatively prominent interaction and the strength is often comparable to H-bond).

They are irrelevant to the warning.

Without full output file, I cannot answer the actual reason.

By the way, using Shermo to calculate thermodynamic quantities based on Gaussian output file of "freq" task is more recommended, see http://sobereva.com/soft/shermo