Institutt for kjemi: Recent submissions
Now showing items 121-140 of 611
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Effektive læringsstrategier: Innsikter, implementering og tverrfaglig erfaringsutveksling
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-11-18)Forskning på læring viser tydelig at noen læringsstrategier er mer effektive enn andre. To spesielt effektive læringsstrategier er å hente fram fra hukommelsen gjennom for eksempel testing (retrieval practice) og fordeling av læringen over en lengre periode med jevne mellomrom (distributed practice). Forskning viser imidlertid også at studenter i liten grad er bevisste på hva som er mest effektiv ... -
QTAIM analysis dataset for non-covalent interactions in curan clusters
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-21)Furan clusters are very important to understand the dynam- ics and properties of the furan solvent. They can be used combined with quantum cluster equilibrium theory to theo- retically determine the thermodynamics properties of the fu- ran solvent. To understand the structures of the furan clus- ters, one needs to understand the non-covalent interactions that hold the furan molecules together. ... -
Twist-Bent Bonds Revisited: Adiabatic Ionization Potentials Demystify Enhanced Reactivity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-10-11)Explicit calculations of vertical and adiabatic ionization potentials of cyclopropane derivatives with modern DFT methods have underscored the possibility of unusually large reorganization energies (defined as the difference between vertical and adiabatic ionization potentials) of 0.5–1.0 eV for several compounds. Such is the case for ionization of the twist-bent σ-bond of trans-bicyclo[4.1.0]hept-3-ene ... -
Review of DFT-simulated and experimental electrochemistry properties of the polypyridyl Row-1 Mn, Fe & Co, and Group-8 Fe, Ru and Os MLCT complexes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-30)Ruthenium had up to date been pivotal in electro- and photocatalytic applications involving reduction of CO<sub>2</sub> and H<sub>2</sub>O, and dye-sensitized solar cells. Commercial applications would seek use of earth-abundant metals instead. Towards this goal, it is key to review the synthesis, electrochemical and spectroscopical properties of associated metal-to-ligand charge transfer complexes ... -
Exact two-component Hamiltonians for relativistic quantum chemistry: Two-electron picture-change corrections made simple
(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
(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
(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
(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
(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
(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
(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
(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
(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
(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)
(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
(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
(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
(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
(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
(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 ...