Blar i NTNU Open på forfatter "Koch, Henrik"

Viser treff 41-54 av 54

    • Probing ultrafast ππ*/nπ* internal conversion inorganic chromophores via K-edge resonantabsorption 

      Koch, Henrik; Myhre, Rolf H.; Coriani, Sonia (Journal article; Peer reviewed, 2017)
      Many photoinduced processes including photosynthesis and human vision happen in organic molecules and involve coupled femtosecond dynamics of nuclei and electrons. Organic molecules with heteroatoms often possess an important ...

    • Quantum Chemical Calculations on the Physisorption of Molecular Hydrogen on N-doped Graphene 

      Tveeikrem, Marit Elise Endresen (Master thesis, 2013)
      We have investigated the hydrogen storage ability of nitrogen substituted graphene, through studieson the adsorption by performing quantum chemistry calculations on the model system using the aug-cc-pVDZ basis set at MP2 ...

    • Real-time coupled-cluster approaches for electronic multiphoton processes in atoms and molecules 

      Skeidsvoll, Andreas Sæther (Doctoral theses at NTNU;2023:227, Doctoral thesis, 2023)
      This thesis explores time-dependent coupled cluster (TDCC) and time-dependent equation-of-motion coupled cluster (TD-EOM-CC) methods in quantum chemistry. As part of the thesis work, these methods were integrated into the ...

    • Reduced orbital space coupled cluster calculations using a multilevel Hartree-Fock wave function 

      Sæther, Sandra (Master thesis, 2017)
      Embedding, or multilevel, schemes have become exceedingly popular in recent years. The idea is to divide the system into an active part, which is treated by an accurate quantum mechanical method, and then treat the rest ...

    • Resolving the Notorious Case of Conical Intersections for Coupled Cluster Dynamics 

      Kjønstad, Eirik Fadum; Koch, Henrik (Journal article; Peer reviewed, 2017)
      The motion of electrons and nuclei in photochemical events often involves conical intersections, or degeneracies between electronic states. They serve as funnels in nuclear relaxation processes where the electrons and ...

    • Solvent Effects on Optical Rotation: On the Balance between Hydrogen Bonding and Shifts in Dihedral Angles 

      Haghdani, Shokouh; Hoff, Bård Helge; Koch, Henrik; Åstrand, Per-Olof (Journal article; Peer reviewed, 2017)
      Optical rotations of several conformers of four fluorinated molecules containing the 1-naphthalene or 4-(benzyloxy)phenyl group at the stereocenter have been calculated both in the gas phase and in an aqueous environment. ...

    • Spin adapted implementation of EOM-CCSD for triplet excited states: Probing intersystem crossings of acetylacetone at the carbon and oxygen K-edges 

      Faber, Rasmus; Kjønstad, Eirik Fadum; Koch, Henrik; Coriani, Sonia (Journal article; Peer reviewed, 2019)
      We present an equation of motion coupled cluster singles and doubles approach for computing transient absorption spectra from a triplet excited state. The implementation determines the left and right excitation vectors by ...

    • Spin-adapted Open-shell Coupled Cluster Theory 

      Sannes, Bendik Støa (Master thesis, 2022)
      Åpenskall-molekyler er av stor interesse ettersom de gjennomgående opptrer i kjemi, særlig når det kommer til reaksjonsmekanismer hvor bindinger dannes og brytes. En nøyaktig beskrivelse av slike molekyler er derfor viktig ...

    • Strong Coupling in Chiral Cavities: Nonperturbative Framework for Enantiomer Discrimination 

      Riso, Rosario Roberto; Grazioli, Laura; Ronca, Enrico; Giovannini, Tommaso; Koch, Henrik (Peer reviewed; Journal article, 2023)
      The development of efficient techniques to distinguish mirror images of chiral molecules (enantiomers) is very important in both chemistry and physics. Enantiomers share most molecular properties except, for instance, the ...

    • Symmetric Coupled Cluster Theory 

      Kjønstad, Eirik Fadum (Master thesis, 2016)
      We introduce a novel coupled cluster formulation for the ground state, symmetric coupled cluster (SCC) theory, and an extension to excited states, molecular properties, and transition elements called symmetric equation of ...

    • The Dalton quantum chemistry program system 

      Aidas, Kestutis; Angeli, Celestino; Bak, Keld L.; Bakken, Vebjørn; Bast, Radovan; Boman, Linus; Christiansen, Ove; Cimiraglia, Renzo; Coriani, Sonja; Dahle, Pål; Dalskov, Erik K.; Ekström, Ulf Egil; Enevoldsen, Thomas; Eriksen, Janus J.; Ettenhuber, Patrick; Fernández, Berta; Ferrighi, Lara; Fliegl, Heike; Frediani, Luca; Hald, Kasper; Halkier, Asger; Hattig, Christof; Heiberg, Hanne; Helgaker, Trygve; Hennum, Alf Christian; Hettema, Hinne; Hjertenæs, Eirik; Høst, Stine; Høyvik, Ida Marie; Iozzi, Maria Francesca; Jansik, Brannislav; Jensen, Hans-Jørgen Aa.; Jonsson, Dan Johan; Jørgensen, Poul; Kauczor, Johanna; Kirpekar, Sheela; Kjærgaard, Thomas; Klopper, Wim; Knecht, Stefan; Kobayashi, Rika; Koch, Henrik; Kongsted, Jacob; Krapp, Andreas; Kristensen, Kasper; Ligabue, Andrea; Lutnæs, Ola B.; Melo, Juan I.; Mikkelsen, Kurt V.; Myhre, Rolf Heilemann; Neiss, Christian; Nielsen, Christian B.; Norman, Patrick; Olsen, Jeppe; Olsen, Jogvan Magnus H.; Osted, Anders; Packer, Martin J.; Pawlowski, Filip; Pedersen, Thomas Bondo; Provasi, Patricio F.; Reine, Simen Sommerfelt; Rinkevicius, Zilvinas; Ruden, Torgeir A.; Ruud, Kenneth; Rybkin, Vladimir V.; Salek, Pawel; Samson, Claire C. M.; Sanchez de Meras, Alfredo; Saue, Trond; Sauer, Stephan P. A.; Schimmelpfennig, Bernd; Sneskov, Kristian; Steindal, Arnfinn Hykkerud; Sylvester-Hvid, Kristian O.; Taylor, Peter R.; Teale, Andrew M.; Tellgren, Erik; Tew, David P.; Thorvaldsen, Andreas J.; Thøgersen, Lea; Vahtras, Olav; Watson, Mark A.; Wilson, David J. D.; Ziolkowski, Marcin; Ågren, Hans (Journal article; Peer reviewed, 2014)
      Dalton is a powerful general-purpose program system for the study of molecular electronic structure at the Hartree–Fock, Kohn–Sham, multiconfigurational self-consistent-field, Møller–Plesset, configuration-interaction, and ...

    • The persistent spin helix in the presence of hyperfine interactions 

      Qvist, Jørgen Holme (Master thesis, 2018)
      We study the effect of hyperfine interaction in the persistent spin helix (PSH) by investigating the nuclear spin pumping caused by non-equilibrium electron spin dynamics. In the first two chapters we rederive, based on ...

    • Transient Resonant Auger-Meitner Spectra of Photoexcited Thymine 

      Wolf, Thomas J. A.; Paul, Alexander Christian; Folkestad, Sarai Dery; Myhre, Rolf Heilemann; Cryan, James P.; Berrah, Nora; Bucksbaum, Philip H.; Coriani, Sonia; Coslovich, Giacomo; Feifel, Raimund; Martinez, Todd J.; Moeller, Stefan P.; Mucke, Melanie; Obaid, Razib; Plekan, Oksana; Squibb, Richard; Koch, Henrik; Gühr, Markus (Journal article; Peer reviewed, 2021)
      We present the first investigation of excited state dynamics by resonant Auger–Meitner spectroscopy (also known as resonant Auger spectroscopy) using the nucleobase thymine as an example. Thymine is photoexcited in the UV ...

    • Using Localized Molecular Orbitals in the Multi-level Coupled Cluster Approach 

      Stakvik, Linda (Master thesis, 2016)
      In multi-level coupled cluster theory local orbitals have traditionally been generated us- ing Cholesky decomposition of the Hartree-Fock density matrix. Orbitals obtained through Cholesky decomposition are not very local ...