• 2-Chloro-2-phenylethylammonium chloride 

      Lejon, Tore Sigvard; Ingebrigtsen, Truls Erik; Hansen, Lars Kr (Journal article; Tidsskriftartikkel; Peer reviewed, 2006)
    • 3,4-Dihydroquinoxalin-2-ones: recent advances in synthesis and bioactivities 

      Kristoffersen, Tone; Hansen, Jørn H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-26)
      A summary of recent synthesis approaches to 3,4-dihydroquinoxaline-2-ones is discussed herein along with highlights of biological activity. The synthetic approaches include access to enantiopure heterocycles from chiral pool amino acids via coupling/cyclization, Michael addition/cyclization cascades, 3,3-disubstituted systems from multicomponent couplings, Bargellini reaction or photochemical ...
    • 3-(Acetylamino)benzoic acid 

      Hansen, Lars Kr; Perlovich, German; Bauer-Brandl, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2007)
    • (3aS,4S,6S,7aR)-hexahydro-3a,5,5-trimethyl-2-phenyl-4,6-methano-1,3,2-benzodioxaborole 

      Lejon, Tore; Gozhina, Olga Vladimirovna; Khrustalev, Victor N. (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      The molecule of the title compound, C16H21BO2, comprises a chiral fused tricyclic system containing five-membered (1,3,2-dioxaborolane), six-membered (cyclohexane) and four-membered (cyclobutane) rings. The 1,3,2-dioxaborolane ring is almost planar (r.m.s. deviation = 0.035 Å), and the syn H and Me substituents at this ring are in an eclipsed conformation. The cyclohexane and cyclobutane rings adopt ...
    • 4-Hydroxybenzamide 

      Hansen, Lars Kr; Perlovich, German; Bauer-Brandl, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2007)
    • 7-Azathieno[2,3-c] cinnoline 

      Hansen, Lars Kr; Stockmann, V; Fiksdahl, A (Journal article; Tidsskriftartikkel; Peer reviewed, 2007)
    • 7-azathieno[3,2-c]cinnoline 

      Hansen, Lars Kr; Stockmann, V; Fiksdahl, A (Journal article; Tidsskriftartikkel; Peer reviewed, 2007)
    • Ab initio and relativistic DFT study of spin–rotation and NMR shielding constants in XF6 molecules, X = S, Se, Te, Mo, and W 

      Ruud, Kenneth; Demissie, Taye Beyene; Jaszunski, Michal (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Ab initio studies of two pyrimidine derivatives as possible photo-switch systems 

      Csehi, András; Woywod, Clemens Joachim; Halász, Gábor J.; Vibok, Agnes (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The six lowest lying electronic singlet states of 8-(pyrimidine-2-yl)quinolin-ol and 2-(4-nitropyrimidine-2- yl)ethenol have been studied theoretically using the complete active space self-consistent-field (CASSCF) and Møller-Plesset second-order perturbation theory (MP2) methods. Both molecules can be viewed as consisting of a frame and a crane component. As a possible mechanism for the excited-state ...
    • Ab initio wavefunctions in bioinorganic chemistry : more than a succes d'estime? 

      Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
      Dedicated to the memory of Björn Roos (1937–2010), one of the fathers of modern multiconfigurational quantum chemistry, who also cared deeply about chemical applications, and a fun and inspiring friend to countless theoretically oriented chemists.
    • Absolute NMR shielding scales and nuclear spin–rotation constants in 175LuX and 197AuX (X= 19F, 35Cl, 79Br and 127I) 

      Demissie, Taye Beyene; Jaszuński, Michal; Komorovsky, Stanislav; Repisky, Michal; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-28)
      We present nuclear spin–rotation constants, absolute nuclear magnetic resonance (NMR) shielding constants, and shielding spans of all the nuclei in 175LuX and 197AuX (X = 19F, 35Cl, 79Br, 127I), calculated using coupled-cluster singles-and-doubles with a perturbative triples (CCSD(T)) correction theory, four-component relativistic density functional theory (relativistic DFT), and non-relativistic DFT. ...
    • Accurate prediction of emission energies with TD-DFT methods for platinum and iridium OLED materials 

      Morello, Glenn Robert (Journal article; Tidsskriftartikkel, 2017-05-02)
      Accurate prediction of triplet excitation energies for transition metal complexes has proven to be a difficult task when confronted with a variety of metal centers and ligand types. Specifically, phosphorescent transition metal light emitters, typically based on iridium or platinum, often give calculated results of varying accuracy when compared to experimentally determined T1 emission values. ...
    • An Acylation-Finkelstein Approach to Radioiodination of Bioactives: The Role of Amide Group Anchimeric Assistance 

      Fjellaksel, Richard; Dugalic, Damir; Demissie, Taye Beyene; Riss, Patrick; Hjelstuen, Ole Kristian; Sundset, Rune; Hansen, Jørn H (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-28)
      Herein, we report a straightforward sequential acylation‐Finkelstein approach to achieve iodination of amine containing bioactives. The utility was demonstrated by successful radiolabelling with <sup>123</sup>I in high radiochemical yield. Moreover, microwave‐assisted Finkelstein reaction can be employed to enhance conversion and reaction rates to obtain the desired iodides. The method is of interest ...
    • Adaptive order polynomial algorithm in a multi-wavelet representation scheme 

      Durdek, Antoine Pacifique Romain; Jensen, Stig Rune; Juselius, Jonas; Wind, Peter; Flå, Tor; Frediani, Luca (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Aldol condensations on a 3-alkylidene-2,5-diketopiperazine - synthesis of two marine natural products 

      Fairhurst, Magnus John E.; Muhammad, Zeeshan; Haug, Bengt Erik; Bayer, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-06)
      The synthesis of two marine natural products containing a 3-alkylidene-6-arylidene-2,5-diketopiperazine scaffold by employing two consecutive aldol condensations starting with 1,4-diacetyl-2,5-diketopiperazine is reported. The target compounds contain a phenol or an imidazole group as aryl substituents, respectively, and suitable conditions for the aldol condensation of 1-acyl-3-alkylidene-2,5-dik ...
    • Analytic calculations of anharmonic infrared and Raman vibrational spectra 

      Cornaton, Yann; Ringholm, Magnus; Louant, Orian; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-01-07)
      Using a recently developed recursive scheme for the calculation of high-order geometric derivatives of frequency-dependent molecular properties [Ringholm et al., J. Comp. Chem., 2014, 35, 622], we present the first analytic calculations of anharmonic infrared (IR) and Raman spectra including anharmonicity both in the vibrational frequencies and in the IR and Raman intensities. In the case of anharmonic ...
    • Analytic calculations of hyper-Raman spectra from density functional theory hyperpolarizability gradients 

      Ringholm, Magnus; Bast, Radovan; Oggioni, Luca; Ekström, Ulf Egil; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Analytic cubic and quartic force fields using density-functional theory 

      Ringholm, Magnus; Jonsson, Dan Johan; Bast, Radovan; Gao, Bin; Thorvaldsen, Andreas johan; Ekstrøm, Ulf; Helgaker, Trygve; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Analytic density functional theory calculations of pure vibrational hyperpolarizabilities: The first dipole hyperpolarizability of retinal and related molecules 

      Gao, Bin; Ringholm, Magnus; Bast, Radovan; Ruud, Kenneth; Thorvaldsen, Andreas johan; Jaszuński, Michał (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-01-09)
      We present a general approach for the analytic calculation of pure vibrational contributions to the molecular (hyper)polarizabilities at the density-functional level of theory. The analytic approach allows us to study large molecules, and we apply the new code to the study of the first dipole hyperpolarizabilities of retinal and related molecules. We investigate the importance of electron ...
    • Analytic evaluation of the dipole Hessian matrix in coupled-cluster theory 

      Jagau, TC; Gauss, J; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      The general theory required for the calculation of analytic third energy derivatives at the coupled-cluster level of theory is presented and connected to preceding special formulations for hyperpolarizabilities and polarizability gradients. Based on our theory, we have implemented a scheme for calculating the dipole Hessian matrix in a fully analytical manner within the coupled-cluster singles and ...