Dear Samaneh Bagheri,

Multiwfn (http://multiwfn.codeplex.com) is very useful for electronic excitation analysis, see Section 3.21 of its manual for related theories and Section 4.18 for examples. The analysis method proposed in "A Qualitative Index of Spatial Extent in Charge-Transfer Excitations" has also been fully supported by Multiwfn in its main function 18.

In addition, after you load the .wfn file corresponding to excited state or ground state into Multiwfn, using its main function 1, 3, 4 and 5, you can easily obtain electron density value at particular points, plot electron density in a line, in a plane or visualize its isosurface.

Tian Lu

In order to obtain electron densities or population analysis of excited states (obtained from CI or TD-DFT calculation), you must put in the input the next keywords. In this example I wanna to obtain density of second singlet state due to vertical transition and population analysis in the S2 excited state in order to calculate charge transfer with the S0 ground state, then you will calculate two jobs.

td=(singlets,nstates=6,root=2) density=current pop=(nbo,reg)

root=2 indicates the state of interest

density=current indicate that density for population analysis corresponds to root=2

enjoy the keywords!

thank you for your answer. i checked all keyword of Density for a example molecule. but i do not know how electron density in ground state or excited state or for example transition density(density=transition=N) can be determine exactly ? is there this value in output file or not?

Dear Samaneh...

electron density is a global property, so that do not exist in output a value to the individual atoms. You remember that electron density is generated by square of all occupied molecular orbitals, and nornmalized to 1. If you wanna condensed values of the electronic structure, you must use the analysis of electron population or a software for electron density partitioning.

dear Diego Cortes-Arriaganda, thanks for your attention.

I read these papers: A Qualitative Index of Spatial Extent in Charge-Transfer Excitations

and " The calculations of excited-state properties with

Time-Dependent Density Functional Theory". in these papers electronic densities associate d to the ground and excited states, the density variation

associated to the electronic transition are calculated by cubegen in gaussian. you can study these papers. I want to know how i can calculate electronic density as functional of (r) ? i have some questions of these papers about electronic density. thanks

Dear Samaneh Bagheri,

Multiwfn (http://multiwfn.codeplex.com) is very useful for electronic excitation analysis, see Section 3.21 of its manual for related theories and Section 4.18 for examples. The analysis method proposed in "A Qualitative Index of Spatial Extent in Charge-Transfer Excitations" has also been fully supported by Multiwfn in its main function 18.

In addition, after you load the .wfn file corresponding to excited state or ground state into Multiwfn, using its main function 1, 3, 4 and 5, you can easily obtain electron density value at particular points, plot electron density in a line, in a plane or visualize its isosurface.

Tian Lu

Dear Tian Lu,

thank you for your attention. I try to study it. If i have a question, i ask you later. thanks

How to calculate population of TDDFT using GAMESS ...?

Please help.

Dear Tian Lu, 

I just came across you multiwfn software; You implemented the computation of the dual descriptor; I thank you very much  for that.

We have since 2005 devised an extension of the dual descriptor using excited states densities: doi: 10.1039/c3cp51169c. it might be of interest to you that we are trying to program a way to compute this extended dual descriptor. 

All the best,