Either make a cub file using the appropriate gaussian tool to get a density value for a grid of equal sized volume elements or make an fchk file using the appropriate gaussian tool. The fchk file has all the shell coordinates, exponents, contraction cooefficients etc from which (I think) you can calculate the density.

The Charge q(N) is available in Gaussian log file. The default is mullken charge calculation. If you need any other scheme e.g., NBO, Chelpg etc you have to use the keyword pop=NBO etc. Hope this helps. 

I wouldn't recommend Mulliken population at all, it is not a reliable method. I would rather use the more popular NBO, Hirshfeld or Chelpg. However, the problem of the last one is that there is no data available for the van der Waals radii of the transition metal atoms. I hope to have helped you.

thank you Debasish Mandal, thank you Diego García-López and Mat Tolladay but i still don't understend how to find population of atoms from output file (.log)

If the job has completed successfully then the population analysis should appear at the end of the .log file in a section marked 'Population analysis using the SCF density.' If the log file doesn't end with the words 'Normal termination of Gaussian' with the date and time then your job has not ended properly and you will need to figure out why.

Mat Tolladay this is the file, can you help me to extract the population  q(N)

from line 13332: NATURAL POPULATIONS: Natural atomic orbital occupancies

The table beneath contains various columns: NAO, Atom, No, etc. For each atom number (3rd column) there are a set of orbitals with occupancy of each orbital given (6th column). Sum the occupancy column for each atom.

Hi Anas,

     If you want to find your population analysis for the Mulliken population analysis, use the Find option in the word processor you are using to read the file and type in Mulliken in the "search" window and that will take you directly to the population analysis.  If you want the NBO analysis, type in the search window the complete phrase Natural Population Analysis.  I believe these are the things that you are looking for.

you have any software .please

M.Govindarajan

[email protected]

There are several software to do this. One of the most powerful is multiwfn. Search with google.

You can easily calculate fukui indices with the GFN-xTB methods as described here:

https://xtb-docs.readthedocs.io/en/latest/sp.html#fukui-index

The program can be obtained free of charge from Stefan Grimme:

https://www.chemie.uni-bonn.de/pctc/mulliken-center/software/xtb/xtb

All best

Eike

thank you very much Eike Caldeweyher