Transition matrices and orbitals from reduced density matrix theory.

摘要: In this contribution, we report two different methodologies for characterizing the electronic structure reorganization occurring when a chromophore undergoes an transition. For first method, start by setting theoretical background necessary to reinterpretation through simple tensor analysis of (i) transition density matrix and (ii) natural orbitals in scope reduced theory. This novel interpretation is made more clear thanks short compendium one-particle theory Fock space. The formalism further applied classes excited states calculation methods, both requiring single-determinant reference, that express state as hole-particle mono-excited configurations expansion, which particle-hole correlation coupled (time-dependent Hartree-Fock/time-dependent functional theory) or not (configuration interaction single/Tamm-Dancoff approximation). second methodology presented paper, introduce complementary concept related transitions with canonical orbitals. Their expression actually reflects cloud polarisation orbital space decomposition based on actual contribution excitations from occupied virtual ones. approach validates our elements terms Euclidean norm elementary vectors linear A proper use these new concepts leads conclusion despite principles underlying their construction, they provide equivalent topological analyses. connexion evidenced illustrations (in)organic dyes analysis.