Search results for " Chemical calculations"

showing 3 items of 3 documents

Preparation and molecular structures of N′-(2-heteroarylmethylidene)-3-(3-pyridyl)acrylohydrazides

2018

Abstract The crystal and molecular structures of N′-(2-furylmethylidene)-3-(3-pyridyl)acrylohydrazide and N′-(2-thienylmethylidene)-3-(3-pyridyl)acrylohydrazide are reported, and the influence of the type of the heteroatom on the aromaticity of the aromatic rings is discussed. Both molecules are nearly planar. The geometry of the acrylohydrazide arrangement is comparable to that of homologous compounds. Density functional theory (DFT) calculations were performed in order to analyze the changes in the geometry of the studied compounds in the crystalline state and for the isolated molecule. The most significant changes were observed in the values of the N–N and C–N bond lengths. The harmonic …

0301 basic medicinecrystal structure010405 organic chemistryChemistryacroylhydrazidesaromaticityGeneral ChemistryX-ray structure determination01 natural sciences0104 chemical sciences03 medical and health sciences030104 developmental biologyPolymer chemistryquantum chemical calculationsdensity functional theoryheteroaryl substituentsZeitschrift für Naturforschung B
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Disclosing the emissive surface traps in green-emitting carbon nanodots

2021

Abstract The bright photoluminescence of surface-functionalized carbon nanoparticles, known as carbon nanodots (CDs), has been studied for more than a decade because of its fundamental photo-physical interest and strong technological potential. However, the essential nature of the electronic states involved in their typical light emission remains very elusive. Here, we provide conclusive evidence that surface carboxylic moieties are the key to CD fluorescence. The synergy of nanosecond and femtosecond optical studies, cryogenic fluorescence, computational investigations and chemical engineering of a strategically chosen model CD system, allows to demonstrate that their visible-light transit…

Surface (mathematics)PhotoluminescenceMaterials scienceCryogenic studieschemistry.chemical_element02 engineering and technologyGeneral ChemistryNanosecond010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesFluorescenceFluorescence0104 chemical sciencesElectron transferchemistryChemical physicsFemtosecondFemtosecond spectroscopyCarbon dotsGeneral Materials ScienceLight emissionQuantum chemical calculations0210 nano-technologyCarbon
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OpenMolcas: From Source Code to Insight

2019

In this article we describe the OpenMolcas environment and invite the computational chemistry community to collaborate. The open-source project already includes a large number of new developments realized during the transition from the commercial MOLCAS product to the open-source platform. The paper initially describes the technical details of the new software development platform. This is followed by brief presentations of many new methods, implementations, and features of the OpenMolcas program suite. These developments include novel wave function methods such as stochastic complete active space self-consistent field, density matrix renormalization group (DMRG) methods, and hybrid multico…

Wave functionSource codeField (physics)Computer sciencemedia_common.quotation_subjectInterfacesSemiclassical physics010402 general chemistry0601 Biochemistry and Cell Biology01 natural sciencesComputational scienceNOChemical calculationsMathematical methodschemical calculations ; electron correlation ; interfaces ; mathematical methods ; wave function0103 physical sciences0307 Theoretical and Computational ChemistryPhysical and Theoretical ChemistryWave functionWave function Interfaces Chemical calculations Mathematical methods Electron correlationComputingMilieux_MISCELLANEOUSmedia_commonChemical Physics010304 chemical physicsBasis (linear algebra)business.industryDensity matrix renormalization groupElectron correlationSoftware development0803 Computer Software0104 chemical sciencesComputer Science ApplicationsVisualization[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistrybusiness
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