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linsina

Member

Registered: 2025-03-25

Posts: 1

Issue with Obtaining Promolecule Energy in sobEDA

Dear Tian

I have been trying to use sobEDA with quantum chemistry programs other than Gaussian, as I currently do not have access to it. However, I encountered a challenge when calculating the promolecule energy.

From my understanding of sobEDA.sh, after combining fragment wavefunctions, promolecule energy is computed in Gaussian by suppressing orthogonalization. If this is correct, then the issue arises because, to my knowledge, no freely available quantum chemistry program currently offers an option to suppress orthogonalization. As a result, it seems that only Δ_orb can be obtained, while the other energy components are lost.

Would there be any alternative approach to correctly compute the promolecule energy in sobEDA using freely available quantum chemistry software that to my knowledge don't have an option for suppressing orthogonalization?

Best

Last edited by linsina (2025-03-26 09:27:43)

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 2,011

Website

Re: Issue with Obtaining Promolecule Energy in sobEDA

You understanding is correct, an IOp is used to suppress orthogonalization. I didn't notice any freely available program that can suppress the orthogonalization...but I believe there should exist.