Search results for "continuum model"

showing 3 items of 33 documents

Reaction Mechanism of an Intramolecular Oxime Transfer Reaction: A Computational Study

2014

Density functional theory (PBE0/def2-TZVPP) calculations in conjunction with a polarizable continuum model were used to assess the mechanism of the intramolecular oxime transfer reaction that leads to the formation of isoxazolines. Different diastereomers of the intermediates as well as different oximes (formaldehyde and acetone oxime) were considered. The computed reaction profile predicts the water-addition and -expulsion steps as the highest barriers along the pathway, a conclusion that is in line with the experimental evidence obtained previously for these reactions. peerReviewed

polarizable continuum modeldensity-functional theory
researchProduct

A Theoretical and Experimental Investigation of the Spectroscopic Properties of a DNA-Intercalator Salphen-Type ZnIIComplex

2014

The photophysical and DNA-binding properties of the cationic zinc(II) complex of 5-triethylammonium methyl salicylidene ortho-phenylenediiminato (ZnL 2 + ) were investi- gated by a combination of experimental and theoretical methods. DFT calculations were performed on both the ground and the first excited states of ZnL 2 + and on its possi- ble mono- and dioxidation products, both in vacuo and in selected solvents mimicked by the polarizable continuum model. Comparison of the calculated absorption and fluores- cence transitions with the corresponding experimental data led to the conclusion that visible light induces a two-elec- tron photooxidation process located on the phenylenediimi- nato…

spectroscopyNO ligandStereochemistryIntercalation (chemistry)Ionic bondingmetal complex Fluorescence spectroscopy DNA recognition metal complexes organometallics complex formation DNA binding drugs fluorescence spectroscopy equilibrium constants reaction mechanisms nucleic acids affinity binding mode thermodynamics speciationmetal complexesbinding modePhenylenediaminesPolarizable continuum modelCatalysisdrugsmetal complexthermodynamicsintercalationcomplex formationOrganometallic CompoundsA-DNADNA bindingFluorescence spectroscopyDNA recognitionphotochemistryLigandChemistrySpectrum AnalysisphotooxidationOrganic ChemistryCationic polymerizationequilibrium constantsGeneral Chemistrydensity functional calculationFluorescenceZincCrystallographyreaction mechanismsnucleic acidsspeciationSettore CHIM/03 - Chimica Generale E InorganicaExcited stateaffinityfluorescenceorganometallics
researchProduct

Octopus, a computational framework for exploring light-driven phenomena and quantum dynamics in extended and finite systems

2020

Over the last few years, extraordinary advances in experimental and theoretical tools have allowed us to monitor and control matter at short time and atomic scales with a high degree of precision. An appealing and challenging route toward engineering materials with tailored properties is to find ways to design or selectively manipulate materials, especially at the quantum level. To this end, having a state-of-the-art ab initio computer simulation tool that enables a reliable and accurate simulation of light-induced changes in the physical and chemical properties of complex systems is of utmost importance. The first principles real-space-based Octopus project was born with that idea in mind,…

spectroscopyPhotonelectronic-structure calculationsComputer sciencespectraQuantum dynamicsmolecular-dynamicsComplex systemGeneral Physics and AstronomyFOS: Physical sciences010402 general chemistryspin01 natural sciencesSettore FIS/03 - Fisica Della MateriaEngineeringTDDFTreal-space0103 physical sciencesoctopusgeneralized gradient approximationPhysical and Theoretical Chemistrydensity-functional theoryMassively parallelQuantumChemical Physicsreal time010304 chemical physicsComputational Physics (physics.comp-ph)scientific software0104 chemical sciencestotal-energy calculationsphysics.comp-phPhysical SciencesChemical Sciencespolarizable continuum modelState of matterSystems engineeringLight drivenDensity functional theoryPhysics - Computational Physics
researchProduct