title: New tools for the systematic analysis and visualization of electronic excitations. II. Applications.
abstract: The excited states of a diverse set of molecules are examined using a collection of newly implemented analysis methods. These examples expose the particular power of three of these tools: (i) natural difference orbitals (the eigenvectors of the difference density matrix) for the description of orbital relaxation effects, (ii) analysis of the one-electron transition density matrix in terms of an electron-hole picture to identify charge resonance and excitonic correlation effects, and (iii) state-averaged natural transition orbitals for a compact simultaneous representation of several states. Furthermore, the utility of a wide array of additional analysis methods is highlighted. Five molecules with diverse excited state characteristics are chosen for these tasks: pyridine as a prototypical small heteroaromatic molecule, a model system of six neon atoms to study charge resonance effects, hexatriene in its neutral and radical cation forms to exemplify the cases of double excitations and spin-polarization, respectively, and a model iridium complex as a representative metal organic compound. Using these examples a number of phenomena, which are at first sight unexpected, are highlighted and their physical significance is discussed. Moreover, the generality of the conclusions of this paper is verified by a comparison of single- and multireference ab initio methods.
authors.affiliation: Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Plasser
authors.affiliation: Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany.
authors.forename: Stefanie A
authors.initials: SA
authors.lastname: Bäppler
authors.affiliation: Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Wormit
authors.affiliation: Interdisciplinary Center for Scientific Computing, Ruprecht-Karls-University, Im Neuenheimer Feld 368, 69120 Heidelberg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Dreuw