Multiwfn forum

waliabhu

Member

Registered: 2019-03-21

Posts: 1

Electron excitation analysis using CAS output

is it possible to do all the excited state analysis using CASSCF/CASCI output files from Gaussian or ORCA , rather than using CIS/DFT output files? Is it reasonable?

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,773

Website

Re: Electron excitation analysis using CAS output

All methods that rely on loading coefficients of configuration functions cannot be applied to these methods, such as hole-electron analysis and NTO analysis. However, there are some general excitation state analyses method in Multiwfn, for example, the analysis based on density difference between excited state and ground state (introduced in Section 3.21.3 and illustrated in Section 4.18.3 of the manual). To carry out this analysis, you need to provide wavefunction file containing natural orbitals of CASSCF/CASCI type for ground state and excited state, respectively.