Search results for "ABL"

showing 10 items of 13111 documents

A QM/MM Approach Using the AMOEBA Polarizable Embedding: From Ground State Energies to Electronic Excitations

2016

International audience; A fully polarizable implementation of the hybrid Quantum Mechanics/Molecular Mechanics approach is presented, where the classical environment is described through the AMOEBA polarizable force field. A variational formalism, offering a self-consistent 1 relaxation of both the MM induced dipoles and the QM electronic density is used for ground state energies and extended to electronic excitations in the framework of Time-Dependent Density Functional Theory combined with a state specific response of the classical part. An application to the calculation of the solvatochromism of the pyridinium N-phenolate betaine dye used to define the solvent ET30 scale is presented. Th…

010304 chemical physicsChemistryPolarizable force fieldSolvatochromismQuantum Chemistry010402 general chemistryElementary chargeQM/MM01 natural sciences0104 chemical sciencesComputer Science Applications[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistryQM/MMQM/MM; Polarisable embedding; Physical and Theoretical ChemistryPolarizabilityQuantum mechanics0103 physical sciencesPolarisable embeddingDensity functional theorypolarizable force field AMOEBAPhysical and Theoretical ChemistryGround stateExcitationElectronic densityJournal of Chemical Theory and Computation
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Quantum dynamics of 16O in collision with ortho- and para-17O17O

2017

Abstract We report full quantum dynamical observables, such as integral and differential cross sections and rate constants, for the 16 O +  17 O 17 O reactive collision process. We particularly emphasize the effect coming from the nonzero nuclear spin of 17 O, leading to two nuclear spin isomers of 34 O 2 , ortho- and para- 34 O 2 which can be studied independently and behave differently. A comparison with the 16 O +  18 O 18 O collision is given. We find that processes involving 17 O 17 O are always faster than with 18 O 18 O.

010304 chemical physicsChemistryQuantum dynamicsGeneral Physics and AstronomyObservable010402 general chemistryCollision01 natural sciences0104 chemical sciencesReaction rate constant0103 physical sciencesKinetic isotope effectPhysical chemistryPhysical and Theoretical ChemistryAtomic physicsQuantumChemical Physics Letters
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Assembling Halogen-Bonded Capsules via Cation Exchange

2017

Dr. Lotta Turunen is currently a postdoctoral researcher within Acad. Prof. Kari Rissanen's research group at the University of Jyvaskyla in Finland. Under his supervision, she obtained her MSc in organic chemistry and completed her PhD in chemistry in late September 2017. Her research focused on designing, synthesizing, and characterizing halogen-bonded supramolecular assemblies, capsules, and cages.

010405 organic chemistryChemistryGeneral Chemical EngineeringBiochemistry (medical)Supramolecular chemistryNanotechnologyGeneral Chemistry010402 general chemistry01 natural sciencesBiochemistry0104 chemical sciencesGroup (periodic table)HalogenMaterials ChemistryEnvironmental ChemistryOrganic chemistryChem
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Structure effects induced by high mechanical compaction of STAM-17-OEt MOF powders

2021

Financial support by PJ-RIC-FFABR_2017 and the EPSRC grant EPSRC industrial CASE award (grant EP/N50936X/1) are acknowledged. The research programme Nanoporous materials (P1-0021) financially supported by Slovenian Research Agency (ARRS) is acknowledged as well. Metal-organic frameworks (MOFs) are promising materials for many potential applications, spacing from gas storage to catalysis. However, the powder form of which they are generally made is not suitable, mainly because of the low packing density. Powder compaction is therefore necessary, but also challenging because of their typical mechanical fragility. Indeed, generally, they undergo irreversibly damages upon densification processe…

010405 organic chemistryChemistryNanoporousCompactionNanotechnologyFlexible MOFs3rd-DASMetal-organic frameworks010402 general chemistryMOF stabilityQD Chemistry01 natural sciencesMOF tableting0104 chemical sciencesInorganic ChemistryQDMOF TabletingEPR spectroscopy
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Towards the synthesis of substituted porphyrins by a pyridyl group bearing a reactive functionality

2010

Pyridyl-substituted porphyrins bearing a reactive functionality were prepared via Suzuki cross-coupling reactions and resulted in very good yields. These compounds are precursors of new porphyrin architectures able to coordinate two metals: one in the porphyrin core and the second around the pyridyl moiety. During the coupling reactions, a higher reactivity of a chloro picolyl group was evidenced compared to a bromo function on the same reacting molecule.

010405 organic chemistryChemistryStereochemistry[CHIM.ORGA]Chemical Sciences/Organic chemistryGeneral Chemistry010402 general chemistry01 natural sciencesPorphyrinCoupling reaction0104 chemical sciencesA3B-porphyrinschemistry.chemical_compoundSuzuki reactionGroup (periodic table)[ CHIM.ORGA ] Chemical Sciences/Organic chemistryPolymer chemistrypolycyclic compoundsMoietyMoleculeheterocyclic compoundsReactivity (chemistry)meso-functionalizationSuzuki couplingpyridyl substituted porphyrinsComputingMilieux_MISCELLANEOUS
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Cis- and trans molybdenum oxo complexes of a prochiral tetradentate aminophenolate ligand : Synthesis, characterization and oxotransfer activity

2020

Abstract Reaction of [MoO2Cl2(dmso)2] with the tetradentate O2N2 donor ligand papy [H2papy = N-(2-hydroxybenzyl)-N-(2-picolyl)glycine] leads to formation of the dioxomolybdenum(VI) complex [MoO2(papy)] (1) as a mixture of cis and trans isomers. Recrystallization from methanol furnishes solid cis-1, whereas the use of a dichloromethane-hexane mixture allows for the isolation of the trans-1 isomer. Both isomers have been structurally characterized by X-ray crystallography and the energy difference between the isomeric pair has been investigated by electronic structure calculations. Optimization of two configurational isomers in the gas phase predicts the trans isomer to lie 2.5 kcal/mol lower…

010405 organic chemistryChemistrycomputational modellingStereoisomerism010402 general chemistry01 natural sciencesMedicinal chemistry0104 chemical sciencesCatalysisInorganic ChemistrySolventvariable temperature NMRTripodal ligandepoxidationMaterials ChemistryTheoretical chemistryProton NMRtripodal ligandPhysical and Theoretical ChemistryIsomerizationOxo Atom TransferCis–trans isomerism
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The Cu(II) complex of a C-lipophilized 13aneN4 macrocycle with an additional protonable amino group as micellar anion receptor.

2009

Three 13aneN4 macrocyclic ligands have been prepared bearing a -CH(2)NHR side arm (R = H, n-C(5)H(11), n-C(10)H(21)) on a carbon atom. When Cu(2+) is complexed in the macrocyclic ring, the amino group of the side arm undergoes an acid-base protonation equilibrium but it is not able to coordinate apically the metal cation even when it is deprotonated. The Cu(2+) complex with the ligand bearing the longest appended aliphatic chain is fully confined inside Triton X-100 micelles, and its ability to bind and sequestrate a series of anions inside micelles has been studied at two different pH values, i.e. both with protonated and neutral side-arm amino group. The favourable role played by the prot…

010405 organic chemistryLigandStereochemistryChemistryProtonation010402 general chemistryRing (chemistry)01 natural sciencesMicelle0104 chemical sciencesInorganic ChemistryMetalDeprotonationGroup (periodic table)visual_artvisual_art.visual_art_mediumAnion receptorDalton transactions (Cambridge, England : 2003)
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Electrochemical Arylation Reaction

2018

Arylated products are found in various fields of chemistry and represent essential entities for many applications. Therefore, the formation of this structural feature represents a central issue of contemporary organic synthesis. By the action of electricity the necessity of leaving groups, metal catalysts, stoichiometric oxidizers, or reducing agents can be omitted in part or even completely. The replacement of conventional reagents by sustainable electricity not only will be environmentally benign but also allows significant short cuts in electrochemical synthesis. In addition, this methodology can be considered as inherently safe. The current survey is organized in cathodic and anodic con…

010405 organic chemistryReducing agentGeneral Chemistry010402 general chemistryElectrochemistrySustainable process01 natural sciencesCombinatorial chemistry0104 chemical sciencesAnodeCathodic protectionchemistry.chemical_compoundchemistryReagentOrganic synthesisMetal catalystChemical Reviews
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A thermally/chemically robust and easily regenerable anilato-based ultramicroporous 3D MOF for CO 2 uptake and separation

2021

The combination of the properly designed novel organic linker, 3,6-N-ditriazoyil-2,5-dihydroxy-1,4-benzoquinone (trz2An), with CoII ions results in a 3D ultramicroporous MOF with high CO2 uptake capacity and separation efficiency, with particular attention to CO2/N2 and CO2/CH4 gas mixtures. This material consists of 1D chains of octahedrally coordinated CoII ions linked through the anilato ligands in the equatorial positions and to the triazole substituents from two neighbouring chains in the two axial positions. This leads to a 3D microporous structure with voids with an affinity for CO2 molecules and channels that enable the selective entrance of CO2 but not of molecules with larger kine…

010405 organic chemistryRenewable Energy Sustainability and the EnvironmentUNESCO::QUÍMICAHigh selectivityTriazoleGeneral ChemistryMicroporous materialQuímica010402 general chemistry01 natural sciences:QUÍMICA [UNESCO]0104 chemical sciencesIonchemistry.chemical_compoundAdsorptionchemistryChemical engineeringCarbon dioxideMoleculeGeneral Materials ScienceLinkerMaterialsKinetic diameterJournal of Materials Chemistry A
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A spin-crossover complex based on a 2,6-bis(pyrazol-1-yl)pyridine (1-bpp) ligand functionalized with a carboxylate group

2014

Combining Fe(ii) with the carboxylate-functionalized 2,6-bis(pyrazol-1-yl)pyridine (bppCOOH) ligand results in the spin-crossover compound [Fe(bppCOOH)2](ClO4)2 which shows an abrupt spin transition with a T1/2 of ca. 380 K and a TLIESST of 60 K due to the presence of a hydrogen-bonded linear network of complexes.

010405 organic chemistryStereochemistryLigandSpin transition010402 general chemistry01 natural sciencesMedicinal chemistry3. Good health0104 chemical sciencesInorganic Chemistrychemistry.chemical_compoundLinear networkBPP ligandchemistrySpin crossoverGroup (periodic table)PyridineCarboxylateDalton Transactions
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