Multiwfn forum

mag14011

Member

Registered: 2021-01-18

Posts: 1

Theory behind state-to-state transition dipole calculation

Dear MuliWFN community, can you please direct me to whether in the manual or the literature the theory behind the calculation of electric dipole transition moments between all states (ground-to-excited and excited-to-excited) is described? What does MultiWFN do with basis set and configuration coefficient information to compute this quantity? I've read section 3.21.5, but I want to know more about what MultiWFN is doing, not how to use it, which I already understand. Best regards--MGP

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

Posts: 1,468

Website

Re: Theory behind state-to-state transition dipole calculation

Derivation of transition density matrix (T) between two excited states can be found in Appendix of Section 3.21.9 of Multiwfn manual. Transition electric dipole moment of X component can be simply obtained as ∑{i}∑{j} T(i,j)*Dx(i,j), where i and j are basis function indices, Dx(i,j) is (i,j) element of electric dipole moment integral matrix in X direction between basis functions.