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bilstone

Member

Registered: 2021-05-04

Posts: 3

signature of BCP in AIM Analysis for SO2

Hi
I did a topology analysis of the electron density (= AIM = Bader Analyis) of the SO2 molecule. The analysis finds two symmetry equivalent BCP with signature (3,-1):

However, when I do "7 Show real space function values at specific CP or all CPs" to check the components of the Laplacian, I get only one negative, but two positive eigenvalues:

How can the CP type be (3,-1), when only one of the lambda values is negative?

sobereva

Tian Lu (Multiwfn developer)

From: Athens, Greece

Registered: 2017-09-11

Posts: 2,187

Website

Re: signature of BCP in AIM Analysis for SO2

You should check eigenvalues of Hessian of electron density, rather than Cartesian components of Laplacian of electron density. They are different.