Details

Autor(en) / Beteiligte

• Fernández-Alarcón, Alberto
• Casals-Sainz, José Luis
• Guevara-Vela, José Manuel
• Costales, Aurora
• Francisco, Evelio
• Martín Pendás, Ángel
• Rocha-Rinza, Tomás

Titel

Partition of electronic excitation energies: the IQA/EOM-CCSD method

Ist Teil von

• Physical chemistry chemical physics : PCCP, 2019-06, Vol.21 (25), p.13428-13439

Ort / Verlag

England: Royal Society of Chemistry

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Different developments in chemistry and emerging technologies have generated a renewed interest in the properties of molecular excited states. We present herein the partition of black-box, size-consistent equation-of-motion coupled cluster singles and doubles (EOM-CCSD) excitation energies within the framework of the interacting quantum atoms (IQA) formalism. We denote this method as IQA/EOM-CCSD. We illustrate this approach by considering small molecules used often in the study of excited states. This investigation shows how the combination of IQA and EOM-CCSD may provide valuable insights into the molecular changes induced by electron excitation via the real space distribution of the energy of an absorbed photon in a molecular system. Our results reveal (i) the most energetically deformed atomic basins and (ii) the most affected covalent and non-covalent interactions within a molecule due to a given photoexcitation. In other words, this kind of analysis provides insights into the spatial energetic redistribution accompanying an electronic excitation, with interesting foreseeable applications in the rational design of photoexcitations with tailored chemical effects. Altogether, we expect that the IQA/EOM-CCSD excitation energy partition will prove useful in the understanding of systems and processes of interest in photophysics and photochemistry. We put together equation of motion coupled cluster theory and the interacting quantum atoms electronic energy partition to determine how an absorbed photon changes atomic energies as well as covalent and noncovalent interactions within a molecule or molecular cluster.