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Abdullah

Member

Registered: 2021-01-28

Posts: 32

How to calculate HOMO LUMO gap at MP2 level using ORCA

Hi, from MP2 calculation output file I only get HOMO LUMO orbital energies at SCF density. Is this possible to get orbital energies and HOMO LUMO gap at MP2 level in ORCA?

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,830

Website

Re: How to calculate HOMO LUMO gap at MP2 level using ORCA

It is impossible. MP2 is a post-HF method, which is beyond single-electron approximation and orbital energies cannot be obtained.

Abdullah

Member

Registered: 2021-01-28

Posts: 32

Re: How to calculate HOMO LUMO gap at MP2 level using ORCA

Dear Professor, Thank you very much for the answer.