Viser treff 101-120 av 587

    • Exact two-component Hamiltonians for relativistic quantum chemistry: Two-electron picture-change corrections made simple 

      Knecht, Stefan; Repisky, Michal; Jensen, Hans Jørgen Aagaard; Saue, Trond (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-19)
      Based on self-consistent field (SCF) atomic mean-field (amf) quantities, we present two simple yet computationally efficient and numerically accurate matrix-algebraic approaches to correct both scalar-relativistic and spin–orbit two-electron picture-change effects (PCEs) arising within an exact two-component (X2C) Hamiltonian framework. Both approaches, dubbed amfX2C and e(xtended)amfX2C, allow us ...
    • The four-component DFT method for the calculation of the EPR g-tensor using a restricted magnetically balanced basis and London atomic orbitals 

      Misenkova, Debora; Lemken, Florian; Repisky, Michal; Noga, Jozef; Malkina, Olga L.; Komorovsky, Stanislav (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-28)
      ABSTRACT Four-component relativistic treatments of the electron paramagnetic resonance g-tensor have so far been based on a common gauge origin and a restricted kinetically balanced basis. The results of such calculations are prone to exhibit a dependence on the choice of the gauge origin for the vector potential associated with uniform magnetic field and a related dependence on the basis set ...
    • Data to Understand the Nature of Non-Covalent Interactions in the Thiophene Clusters 

      Malloum, Alhadji; Conradie, Jeanet (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-10)
      We have reported herein the data to understand the nature and number of non-covalent interactions that stabilize the structures of the thiophene clusters. In addition, we have also provided the optimized Cartesian coordinates of all the structures of the investigated thiophene clusters. Initially, the geometries have been generated using the ABCluster code which performs a global optimization to ...
    • Comparing Isoelectronic, Quadruple-Bonded Metalloporphyrin and Metallocorrole Dimers: Scalar-Relativistic DFT Calculations Predict a > 1-eV Range for Ionization Potential and Electron Affinity 

      Conradie, Jeanet; Vazquez-Lima, Hugo; Alemayehu, Abraham; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-21)
      A scalar-relativistic DFT study of isoelectronic, quadruple-bonded Group 6 metalloporphyrins (M = Mo, W) and Group 7 metallocorroles (M = Tc, Re) has uncovered dramatic differences in ionization potential (IP) and electron affinity (EA) among the compounds. Thus, both the IPs and EAs of the corrole derivatives are 1 eV or more higher than those of the porphyrin derivatives. These differences ...
    • Dimethylsulfoxide (DMSO) Clusters Dataset: DFT Relative Energies, Non-Covalent Interactions, and Cartesian Coordinates 

      Malloum, Alhadji; Conradie, Jeanet (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-07)
      Theoretical understanding of dimethylsulfoxide (DMSO) liquid depends on the understanding of the DMSO clusters. In this work, we provide the structures and the energetics of the DMSO clusters. The structures have been generated using ABCluster and further optimized at the MP2/aug-ccpVDZ level of theory. The final structures have been optimized at two different levels of theory: PW6B95D3/aug-ccpVDZ ...
    • Electronic and structural data of 4’-substituted bis(2,2’;6’2’’-terpyridine)manganese in mono-, bis-, tris- and tetra-cationic states from DFT calculations 

      Conradie, Jeanet (Journal article; Tidsskriftartikkel, 2022-04-30)
      This data article provides density functional theory calculated structural (bond lengths and angles, coordinates of optimized geometries) and electronic (Mulliken spin population and character of frontier molecular orbitals) data of a series of 4’-substituted bis(2,2’;6’2’’-terpyridine)manganese complexes in four different oxidation states. The bis-cationic (n = 2) [Mn(tpy)<sub>2</sub>]<sup>2+</sup> ...
    • Electrophilic Activation of Osmium-Nitrido Corroles: The OsN Triple Bond as a π-Acceptor Metallaligand in a Heterobimetallic OsVIN–PtII Complex 

      Reinholdt, Anders; Alemayehu, Abraham; Gagnon, Kevin J.; Bendix, Jesper; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-31)
      Presented herein is a first investigation of the chemical reactivity of osmium-nitrido corroles, which are known for their unusual thermal, chemical, and photochemical stability. Elemental chlorine perchlorinates the β-positions of the triarylcorrole but leaves the OsN unit untouched. The OsN unit is also unaffected by a variety of other electrophilic and nucleophilic reagents. Upon photolysis, ...
    • A concise SAR-analysis of antimicrobial cationic amphipathic barbiturates for an improved activity-toxicity profile 

      Langer, Manuel K; Rahman, Ataur; Dey, Hymonti; Anderssen, Trude; Zilioli, Francesco; Haug, Tor; Blencke, Hans-Matti; Stensvåg, Klara; Strøm, Morten B.; Bayer, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-05)
      An amphipathic barbiturate mimic of the marine eusynstyelamides is reported as a promising class of antimicrobial agents. We hereby report a detailed analysis of the structure-activity relationship for cationic amphipathic N,N′ -dialkylated-5,5-disubstituted barbiturates. The influence of various cationic groups, hydrocarbon linkers and lipophilic side chains on the compounds’ antimicrobial potency ...
    • Comparison of 2- and 3-compartment electrodialytic remediation cells for oil polluted soil from northwest Russia 

      Shouli Pour, Fatemeh; Jensen, Pernille Erland; Pedersen, Kristine Bondo; Lejon, Tore (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-08)
      Electrodialytic remediation is a method based on electrokinetics, in which an electric field of low intensity increases the availability of pollutants in solid waste materials. The electric field induces processes that mobilise and transport inorganic and organic pollutants. The transport of ions in the electrodialytic cell is controlled by employing ion-exchange membranes, allowing separation of ...
    • Our Cup of Tea: Sustainable Organometallic Chemistry 

      Obligacion, Jennifer V.; Hopmann, Kathrin Helen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-25)
      What makes organometallic chemistry sustainable, or at least could make it more sustainable? A practical concept that allows us to set deliverable sustainability goals is Istvan Horváth’s sustainable definition of sustainability: Resources including energy should be used at a rate at which they are replaced naturally and the generation of waste cannot be faster than the rate of their remediation. ...
    • Structural and biophysical analysis of interactions between cod and human uracil-DNA N-glycosylase (UNG) and UNG inhibitor (Ugi) 

      Assefa, Netsanet Gizaw; Niiranen, Laila; Johnson, Kenneth; Leiros, Hanna-Kirsti S.; Smalås, Arne O.; Willassen, Nils Peder; Moe, Elin (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-07-25)
      Uracil-DNA N-glycosylase from Atlantic cod (cUNG) shows cold-adapted features such as high catalytic efficiency, a low temperature optimum for activity and reduced thermal stability compared with its mesophilic homologue human UNG (hUNG). In order to understand the role of the enzyme–substrate interaction related to the cold-adapted properties, the structure of cUNG in complex with a bacteriophage ...
    • Evolution of β-lactamase-mediated cefiderocol resistance 

      Frøhlich, Christopher; Sørum, Vidar; Tokuriki, Nobuhiko; Johnsen, Pål Jarle; Samuelsen, Ørjan (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-11)
      Background: Cefiderocol is a novel siderophore β-lactam with improved hydrolytic stability toward β-lactamases, including carbapenemases, achieved by combining structural moieties of two clinically efficient cephalosporins, ceftazidime and cefepime. Consequently, cefiderocol represents a treatment alternative for infections caused by MDR Gram-negatives.<p> <p>Objectives: To study the role of ...
    • Structure-sensitive marker bands of metallocorroles: A resonance Raman study of manganese and gold corrole derivatives 

      Terner, James; Kolle Ekaney, Thomas; Vazquez Lima, Hugo; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-03)
      Soret-excited resonance Raman spectra (λ<sub>ex</sub> 413.1 nm) were acquired for manganese(III) and gold(III) tris(pentafluorophenyl)corrole, each as four different isotopomeric samples: natural abundance, fully pyrrole-<sup>15</sup>N-substituted, fully meso<sup>13</sup>C-substituted, and fully pyrrole-<sup>15</sup>N-meso<sup>13</sup>C-substituted. The spectra were modeled with density functional ...
    • DYRK1a Inhibitor Mediated Rescue of Drosophila Models of Alzheimer’s Disease-Down Syndrome Phenotypes 

      Zhu, Bangfu; Parsons, Tom; Stensen, Wenche Gunvor Berg; Svendsen, John Sigurd Mjøen; Fugelli, Anders; Hodge, James W.L. (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-19)
      Alzheimer’s disease (AD) is the most common neurodegenerative disease which is becoming increasingly prevalent due to ageing populations resulting in huge social, economic, and health costs to the community. Despite the pathological processing of genes such as Amyloid Precursor Protein (APP) into Amyloid-β and Microtubule Associated Protein Tau (MAPT) gene, into hyperphosphorylated Tau tangles being ...
    • The unique disulfide linked activation loop of DYRK kinases and possible redox activity control 

      Dyrendalsli, Maja Bele (Master thesis; Mastergradsoppgave, 2022-06-15)
      The cysteine of HCD (C286) in DYRK1A is involved in disulfide bridge formation with a cysteine (C312) in the DFGSSC sequence. The purpose of this project was to investigate how the state of the disulfide bridge would affect enzyme catalytic and ligand binding properties of the protein kinase. A mutant, DYRK1A C312A, was thus designed to eliminate the disulfide bridge. The mutant was expressed and ...
    • Structural and functional studies of Ectoine Synthase from Chromohalobacter salexigens DSM 3043 and Marinobacter sp. CK1 

      Gundesø, Sigurd Eidem (Master thesis; Mastergradsoppgave, 2021-10-15)
      Ectoine is a compatible solute found in many microorganisms adapted to survive in saline and other extreme environments. Here, it aids microorganisms to counter osmotic stress and protect their enzymes. Ectoine exhibit many interesting properties that is potentially commercially exploitable, and it is currently produced and found in several products on the market. While ectoine is produced by ...
    • Computer Simulation of Antimicrobial Agents 

      Haugen, Tonje Reinholdt (Master thesis; Mastergradsoppgave, 2021-10-15)
      The last 18 months has shown the impact a single microorganism can have on society with the SARS-CoV-2 virus. This is not the only global threat on our health, with the World Health Organisation and other government agencies warning against the increase in antimicrobial resistance today. Antimicrobial peptides have been seen as a possible solution, as they are known to fight bacteria as a part of ...
    • Tailored Leaching Tests as a Tool for Environmental Management of Mine Tailings Disposal at Sea 

      Pedersen, Kristine B.; Lejon, Tore; Evenset, Anita (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-10)
      The expanding human activities in coastal areas increase the need for developing solutions to limit impacts on the marine environment. Sea disposal affects the marine environment, but despite the growing knowledge of potential impacts, there are still no standardized leaching tests for sea disposal. The aim of this study was to contribute to the development of leaching tests, exemplified using ...
    • Cobalt-Catalyzed Asymmetric Hydrogenation of Enamides: Insights into Mechanisms and Solvent Effects 

      Pavlovic, Ljiljana; Mendelsohn, Lauren N.; Zhong, Hongyu; Chirik, Paul J.; Hopmann, Kathrin Helen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-25)
      The mechanistic details of the (<sup>Ph</sup>BPE)Co-catalyzed asymmetric hydrogenation of enamides are investigated using computational and experimental approaches. Four mechanistic possibilities are compared: a direct Co(0)/Co(II) redox path, a metathesis pathway, a nonredox Co(II) mechanism featuring an azametallacycle, and a possible enamide−imine tautomerization pathway. The results indicate ...
    • Anodic Activity of Hydrated and Anhydrous Iron (II) Oxalate in Li-Ion Batteries 

      Keshavarz, Fatemeh; Kadek, Marius; Barbiellini, Bernardo; Bansil, Arun (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-12)
      We discuss the applicability of the naturally occurring compound Ferrous Oxalate Dihydrate (FOD) (FeC2O4·2H2O) as an anode material in Li-ion batteries. Using first-principles modeling, we evaluate the electrochemical activity of FOD and demonstrate how its structural water content affects the intercalation reaction and contributes to its performance. We show that both Li0 and Li+ intercalation in ...