Now showing items 164-183 of 251

    • Non-nearest neighbour ICD in clusters 

      Fasshauer, Elke (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-04-19)
      Interatomic Coulombic decay (ICD) is an electronic decay process of excited, ionized systems. It has been shown to occur in a multitude of small and large systems. The effects of more than one possible decay partner are discussed in detail illustrated by simulated ICD electron spectra of NeAr clusters and pure Ne clusters. Hereby, the mostly underestimated contribution of decay with non-nearest ...
    • Norcorrole as a Delocalized, Antiaromatic System 

      Conradie, Jeanet; Foroutan-Nejad, Cina; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-19)
      Nickel norcorrole provides an unusual example of a molecule that is strongly antiaromatic according to the magnetic criterion, but which exhibits, according to high-quality DFT calculations, a symmetric, delocalized structure with no difference in bond length between adjacent C<sub>meso</sub>-C<sub>α</sub> bonds. A fragment molecular orbital analysis suggests that these discordant observations are ...
    • Note: Derivation of two-photon circular dichroism - Addendum to "two-photon circular dichroism" [J. Chem. Phys. 62, 1006 (1975)] 

      Friese, Daniel Henrik (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-02)
      This addendum shows the detailed derivation of the fundamental equations for two-photon circular dichroism which are given in a very condensed form in the original publication [I. Tinoco, J. Chem. Phys. 62, 1006 (1975)]. In addition, some minor errors are corrected and some of the derivations in the original publication are commented.
    • Novel antimicrobial peptides EeCentrocins 1, 2 and EeStrongylocin 2 from the Edible sea urchin Echinus esculentus have 6-br-trp post-translational modifications 

      Solstad, Runar Gjerp; Li, Chun; Isaksson, Johan; Johansen, Jostein a; Svenson, Johan; Stensvåg, Klara; Haug, Tor (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-03-23)
      The global problem of microbial resistance to antibiotics has resulted in an urgent need to develop new antimicrobial agents. Natural antimicrobial peptides are considered promising candidates for drug development. Echinoderms, which rely on innate immunity factors in the defence against harmful microorganisms, are sources of novel antimicrobial peptides. This study aimed to isolate and characterise ...
    • On the Application of Bio-Inspired Optimization Algorithms to Fuzzy C-Means Clustering of Time Series 

      Muhammad Fuad, Muhammad Marwan (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)
      Fuzzy c-means clustering (FCM) is a clustering method which is based on the partial membership concept. As with the other clustering methods, FCM applies a distance to cluster the data. While the Euclidean distance is widely-used to perform the clustering task, other distances have been suggested in the literature. In this paper we study the use of a weighted combination of metrics in FCM clustering ...
    • One electron changes the entire story: NMR versus pNMR 

      Demissie, Taye Beyene (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-28)
      <sup>11</sup>B NMR chemical shifts of structurally similar diamagnetic and paramagnetic molecules are obtained using four-component relativistic DFT calculations. The calculated chemical shifts of the diamagnetic molecules are compared with those of the paramagnetic molecules to get an insight on the influence of the unpaired electron on the <sup>11</sup>B chemical shifts.
    • One-Pot Synthesis of a bis-Pocket Corrole through a 14-fold Bromination Reaction. 

      Norheim, Hans-Kristian; Schneider, Christian; Gagnon, Kevin J.; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-02-14)
      A one-pot protocol, effecting 14-fold bromination with elemental bromine, has afforded copper β-octabromo-meso-tris (2,6-dibromo-3,5-dimethoxyphenyl) corrole, a new bis-pocket metallocorrole. The Cu complex underwent smooth demetalation under reductive conditions, affording the free corrole ligand, which in turn could be readily complexed to MnIII and AuIII. A single-crystal X-ray structure was ...
    • One-Step or Two-Step Optimization and the Overfitting Phenomenon:A Case Study on Time Series Classification 

      Muhammad Fuad, Muhammad Marwan (Peer reviewed; Conference object; Konferansebidrag, 2014)
      For the last few decades, optimization has been developing at a fast rate. Bio-inspired optimization algorithms are metaheuristics inspired by nature. These algorithms have been applied to solve different problems in engineering, economics, and other domains. Bio-inspired algorithms have also been applied in different branches of information technology such as networking and software engineering. ...
    • One‐Pot Synthesis of a bis‐Pocket Corrole through a 14‐fold Bromination Reaction 

      Norheim, Hans-Kristian; Schneider, Christian; Gagnon, Kevin J.; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-02-14)
      A one-pot protocol, effecting 14-fold bromination with elemental bromine, has afforded copper beta-octabromo-meso-tris(2,6-dibromo-3,5-dimethoxyphenyl)corrole, a new bis-pocket metallocorrole. The Cu complex underwent smooth demetalation under reductive conditions, affording the free corrole ligand, which in turn could be readily complexed to Mn<sup>III</sup> and Au<sup>III</sup>.A single-crystal ...
    • Open-ended formulation of self-consistent field response theory with the polarizable continuum model for solvation 

      Di Remigio, Roberto; Beerepoot, Maarten; Cornaton, Yann; Ringholm, Magnus; Steindal, Arnfinn Hykkerud; Ruud, Kenneth; Frediani, Luca (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-11-15)
      The study of high-order absorption properties of molecules is a field of growing importance. Quantumchemical studies can help design chromophores with desirable characteristics. Given that most experiments are performed in solution, it is important to devise a cost-effective strategy to include solvation effects in quantum-chemical studies of these properties. We here present an open-ended ...
    • Open-ended recursive approach for the calculation of multiphoton absorption matrix elements 

      Friese, Daniel Henrik; Beerepoot, Maarten T. P.; Ringholm, Magnus; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-02-11)
      We present an implementation of single residues for response functions to arbitrary order using a recursive approach. Explicit expressions in terms of density-matrix-based response theory for the single residues of the linear, quadratic, cubic, and quartic response functions are also presented. These residues correspond to one-, two-, three- and four-photon transition matrix elements. The newly ...
    • Open-Ended Recursive Calculation of Single Residues of Response Functions for Perturbation-Dependent Basis Sets 

      Friese, Daniel Henrik; Ringholm, Magnus; Gao, Bin; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-09)
      We present theory, implementation, and applications of a recursive scheme for the calculation of single residues of response functions that can treat perturbations that affect the basis set. This scheme enables the calculation of nonlinear light absorption properties to arbitrary order for other perturbations than an electric field. We apply this scheme for the first treatment of two-photon circular ...
    • Open-ended response theory with polarizable embedding: multiphoton absorption in biomolecular systems 

      Steindal, Arnfinn Hykkerud; Beerepoot, Maarten; Ringholm, Magnus; List, Nanna Holmgaard; Ruud, Kenneth; Kongsted, Jacob; Olsen, Jógvan Magnus Haugaard (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-09-19)
      We present the theory and implementation of an open-ended framework for electric response properties at the level of Hartree–Fock and Kohn–Sham density functional theory that includes effects from the molecular environment modeled by the polarizable embedding (PE) model. With this new state-of-the-art multiscale functionality, electric response properties to any order can be calculated for molecules ...
    • The optical activity of beta, gamma-enones in ground and excited states using circular dichroism and circularly polarized luminescence 

      Pecul, Magdalena; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
      The circularly polarized luminescence (CPL) and electronic circular dichroism (CD) spectroscopic parameters corresponding to the n ← π* and n → π* transitions, respectively, have been calculated for selected β,γ-enones using density functional theory. For the smallest β,γ-enone, (1R,4R)-bicyclo[2.2.1]hept-5-en-2-one (norbornenone), coupled-cluster calculations have also been carried out. The ...
    • An optimised method for electrodialytic removal of heavy metals from harbour sediments 

      Pedersen, Kristine Bondo; Jensen, Pernille E.; Ottosen, Lisbeth M.; Lejon, Tore (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-10)
      A 2-compartment electrodialytic cell set-up for treatment of solid materials has in many respects proven superior to other types of cells in removing heavy metals from sediments. Most notably, remediation times were shorter, energy consumption was lower and higher removal efficiencies were observed. By employing multivariate modelling and investigating additional experimental variables, the ...
    • The origin dependence of the material constants: the permittivity and the inverse permeability 

      Anelli, Marco; Jonsson, Dan Johan; Fliegl, Heike; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-05-26)
      New derivations of origin-independent expressions for the electric permittivity are presented, starting either from the response function of the current density that defines the absorption coefficient, or from the off-resonance single-photon scattering amplitude that leads to the Kramers–Heisenberg dispersion formula. The resulting expression for the permittivity is compared with earlier work ...
    • Origin of Dual-Peak Phosphorescence and Ultralong Lifetime of 4,6-Diethoxy-2-carbazolyl-1,3,5-triazine 

      Paul, Lopa; Chakrabarti, Swapan; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-02)
      Recently, ultralong phosphorescence lifetime has been observed in 4,6-diethoxy-2-carbazolyl-1,3,5-triazine, and H-aggregation induced stabilization of the T1 state was suggested as its source. The response theory calculations demonstrate that the Davydov stabilization of the T1 state of the dimer is marginal with respect to the monomer and the corresponding transition moments are virtually the same. ...
    • OXA-48-Mediated Ceftazidime-Avibactam Resistance Is Associated with Evolutionary Trade-Offs 

      Frøhlich, Christopher; Sørum, Vidar; Thomassen, Ane Molden; Johnsen, Pål Jarle; Samuelsen, Ørjan (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-27)
      Infections due to carbapenemase-producing Gram-negative pathogens are associated with limited treatment options and consequently lead to increased mortality and morbidity. In response, combinations of existing β-lactams and novel β-lactamase inhibitors, such as ceftazidime-avibactam (CAZ-AVI), have been developed as alternative treatment options. To understand the development of resistance and ...
    • Palladium(0)-Catalyzed Cross-Couplings of 2-Bromophosphinine 

      Kostenko, Nataliya; Eriksson, Cecilia; Engqvist, Magnus; Villa Gonzalez, Susana; Bayer, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-05-21)
      A new Negishi-type cross-coupling of 2-bromophosphinine has been developed. The new method expands the scope of palladium-catalyzed couplings to monobromophosphinines, which have been considered as poor substrates so far. Moreover, aryl-, alkenyl-, and alkynylzinc bromides were found to be effective coupling partners.
    • Pan genome and CRISPR analyses of the bacterial fish pathogen Moritella viscosa 

      Karlsen, Christian; Hjerde, Erik; Klemetsen, Terje; Willassen, Nils Peder (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-20)
      Background: Winter-ulcer Moritella viscosa infections continue to be a significant burden in Atlantic salmon (Salmo salar L.) farming. M. viscosa comprises two main clusters that differ in genetic variation and phenotypes including virulence. Horizontal gene transfer through acquisition and loss of mobile genetic elements (MGEs) is a major driving force of bacterial diversification. To gain insight ...