thanks for your very quick response. This clarifies a lot, and I will return to the relevant sections in your manual (which I very detailed and great to read). Everything you are saying makes sense, especially the comment regarding the basins confirms what we've been doing (and this is reassuring).

I will have some more questions in due course, but for now thanks again.

Tobias

Please carefully check Section 3.18.5 of Multiwfn manual. At the end of the section you will find there is no essential difference between variance and localization index, the latter can be directly outputted by basin analysis module via option "4 Calculate localization index (LI) and delocalization index (DI) for basins". I prefer to use the word "localization index" instead of "variance" since the semantics of the former is a bit clearer.

According to the spatial distribution of basins shown in option 0 of basin analysis module, you can very easily determine the type of a ELF basin, such as V(A), V(A,B), C(A), etc.

Please check the ELF basin analysis example in Section 4.17.2 of manual, you will better understand what I said above.

Best regards,

Tian

I currently working out how to obtain ELF parameters using multiwfn (I have used the code for other things in the past, but not for this purpose). I am wondering how to  obtain information about basin populations, variance and the type of basin (monosynaptic, disynaptic).
I figured that I have to do a basin analysis for ELF (17, 1, 9 in the menu), and once this is completed run and integration over a real space function (electron density). This gives a list of attractors and their populations. However, I havent figured out how to compute other relevant data, such as the variance (which is often used for analysis). Also, is there a better way to output the information, i.e. how can I decide whether to call the basins V(A), V(A,B) etc.? Is this merely a matter of visually inspecting the attractors?

Thanks for your help.

Tobias