Search results for " Functional"

showing 10 items of 1811 documents

cis-[(η5-C5H5)Fe(η1-CO)(μ-CO)]2, the poor relative between cis and trans tautomers. A theoretical study of the gas-phase Fe L3-edge and C and O K-edg…

2021

The relative stability of trans-[(η5-C5H5)Fe(η1-CO)(μ-CO)]2 (trans-I) and cis-I tautomers in a vacuum and in solvents with different dielectric constants (e) has been investigated by exploiting density functional theory (DFT). Theoretical results indicate that, in agreement with experimental evidence, trans-I is more stable than cis-I in a vacuum (∼1.5 kcal mol−1; e = 1), while the opposite is true in media with e > 7. Differently from solution, DFT outcomes pertaining to the vapor-phase cis-I ⇆ trans-I equilibrium at T = 368 K, the temperature at which the Fe L2,3-edges and the C and O K-edge X-ray absorption spectroscopy (XAS) data of I have been recorded, ultimately indicate the trans-I …

X-ray absorption spectroscopyMaterials scienceK-edgeAbsorption spectroscopyGeneral Physics and AstronomyPhysical chemistryDensity functional theoryDielectricPhysical and Theoretical ChemistryTautomerSpectral lineCis–trans isomerismPhysical Chemistry Chemical Physics
researchProduct

X-ray Spectroscopy of (Ba,Sr,La)(Fe,Zn,Y)O3-δIdentifies Structural and Electronic Features Favoring Proton Uptake

2020

Mixed protonic–electronic conducting oxides are key functional materials for protonic ceramic fuel cells. Here, (Ba,Sr,La)(Fe,Zn,Y)O3−δ perovskites are comprehensively investigated by X-ray spectroscopy (in oxidized and reduced states). Extended X-ray absorption fine structure shows that Zn,Y doping strongly increases the tendency for Fe–O–Fe buckling. X-ray absorption near-edge spectroscopy at the Fe K-edge and X-ray Raman scattering at the O K edge demonstrate that both iron and oxygen states are involved when the samples are oxidized, and for the Zn,Y doped materials, the hole transfer from iron to oxygen is less pronounced. This can be correlated with the observation that these material…

X-ray spectroscopyMaterials scienceProtonGeneral Chemical Engineeringchemistry.chemical_element02 engineering and technologyGeneral Chemistry010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesOxygen0104 chemical sciencesExtended X ray absorption fine structure spectroscopy Functional materials Iron OxygenPerovskite Protonic ceramic fuel cells (PCFC) X ray absorptionCrystallographychemistryvisual_artMaterials Chemistryvisual_art.visual_art_mediumFuel cellsCeramicAbsorption (chemistry)0210 nano-technology
researchProduct

Comparative Experimental and Theoretical Study of the Fe L-2,L-3-Edges X-ray Absorption Spectroscopy in Three Highly Popular, Low-Spin Organoiron Com…

2019

The occupied and unoccupied electronic structures of three highly popular, closed shell organoiron complexes ([Fe(CO)(5)], [(eta(5)-C5H5 )Fe(CO)(mu-CO)](2), and [(eta(5)-C5H5)(2)Fe]) have been theoretically investigated by taking advantage of density functional theory (DFT) calculations coupled to the isolobal analogy (Elian et al. Inorg. Chem. 1976, 15, 1148). The adopted approach allowed us to look into the relative role played by the ligand -> Fe donation and the Fe -> ligand back-donation in title molecules, as well as to investigate how CO- (terminal or bridging) and [(eta(5)-C5H5)](-)-based pi* orbitals compete when these two ligands are simultaneously present as in [(eta(5)-C5H…

XASXAS spectroscopy Organoiron complexes DFT.High Resolution X-Ray Absorption SpectroscopyFe L23 edgegas phasedensity functional theory
researchProduct

Zabezpieczenie na nieruchomości w postępowaniu karnym jako wyraz równorzędności reguł interpretacji w praktyce orzeczniczej sądu karnego

2021

Artykuł poddaje analizie instytucję zabezpieczenia na nieruchomości w postępowaniu karnym w kontekście połączenia w niej działania organów postępowania karnego w dwóch różnych procedurach i w dwóch różnych pozycjach procesowych. Zabezpieczenie następuje w zakresie tytułu wykonawczego w postaci stosownego postanowienia i wynika z postępowania karnego w fazie in personam. Tytuł wykonawczy uzyskany w procedurze karnej stanowi podstawę wpisu hipoteki przymusowej według regulacji procedury cywilnej do księgi wieczystej. Artykuł ma na celu przedstawienie powyższej problematyki w kontekście rozkładu ciężaru argumentacyjnego poszczególnych uczestników dyskursu wskazanej sytuacji procesowej, a także…

Zabezpieczenie na nieruchomościsystematic and functional rules of interpretationpostanowienie o zabezpieczeniuburden of argumentationinterpretacja semantyczna i funkcjonalnacriminal proceedingssemantichipoteka przymusowarozkładu ciężaru argumentacyjnegoSecurity on real estatepostępowanie karnepostępowanie cywilnePrzegląd Prawa i Administracji
researchProduct

Y:BaZrO3 Perovskite Compounds I: DFT Study on the Unprotonated and Protonated Local Structures

2011

Y-doped BaZrO(3) derivatives were studied by density functional theory (DFT) to investigate the local arrangements of the octahedral sites in Pm3m cubic frameworks. Single- and double substitution of zirconium by yttrium were considered, including in the presence of a nearby oxygen vacancy. Although the structural symmetry of undoped barium zirconate was not modified after yttrium doping, the presence of yttrium induced several differences in the oxygen sites around it, according to the local geometrical arrangement of yttrium in the host matrix. As an example, the differences between such oxygen sites were shown in the presence of a proton. In this case, different stabilization energies ch…

ZirconiumProtonChemistryProtonic conductionOrganic ChemistryInorganic chemistrychemistry.chemical_elementProtonationyttrium-doped barium zirconateGeneral ChemistryYttriumSiestaBiochemistryDFTCondensed Matter::Materials ScienceCrystallographyOctahedronSettore CHIM/03 - Chimica Generale E InorganicaDensity functional theoryfuel-cellOrder of magnitudeperovskitePerovskite (structure)
researchProduct

Manufacturing and characterization of single cell intermediate-temperature solid oxide fuel cells for APU in transportation application

2014

The fabrications of large area IT-SOFC planar cell by new simple and cost effective process were explained. The optimization of the new process with respect to pore formers, thickness of layers, sintering temperature were performed. The electrochemical results of 10cm2 performed in Fiaxell open flange set up were detailed with respect to different configuration. Long term ageing performance tests of single cells were conducted in Fiaxell device and results are discussed. Preparation of new test bench and stacking process performed till now were briefed.

[ PHYS.PHYS.PHYS-CHEM-PH ] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]CosinteringIT-SOFCTest benchLong term ageing performanceSingle step cell preparation[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]StackTape castingAnode Functional Layer[PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
researchProduct

Towards Iron(II) Complexes with Octahedral Geometry: Synthesis, Structure and Photophysical Properties

2020

The control of ligand-field splitting in iron (II) complexes is critical to slow down the metal-to-ligand charge transfer (MLCT)-excited states deactivation pathways. The gap between the metal-centered states is maximal when the coordination sphere of the complex approaches an ideal octahedral geometry. Two new iron(II) complexes (C1 and C2), prepared from pyridylNHC and pyridylquinoline type ligands, respectively, have a near-perfect octahedral coordination of the metal. The photophysics of the complexes have been further investigated by means of ultrafast spectroscopy and TD-DFT modeling. For C1, it is shown that&mdash

[CHIM.INOR] Chemical Sciences/Inorganic chemistryLigand field theoryCoordination sphereMaterials scienceIronPharmaceutical Scienceexcited states dynamics[CHIM.INOR]Chemical Sciences/Inorganic chemistryCrystallography X-RayLigands010402 general chemistry01 natural sciencesArticletime-resolved spectroscopyAnalytical Chemistrylcsh:QD241-441MetalX-Ray Diffractionlcsh:Organic chemistryDrug DiscoveryOctahedral molecular geometry[CHIM.CRIS]Chemical Sciences/Cristallographyiron (II) complexes[CHIM.COOR]Chemical Sciences/Coordination chemistryFerrous Compounds[CHIM.CRIS] Chemical Sciences/CristallographyPhysical and Theoretical Chemistryoctahedral geometrydensity functional theoryComputingMilieux_MISCELLANEOUSMolecular Structure010405 organic chemistryLigandOrganic Chemistry[CHIM.COOR] Chemical Sciences/Coordination chemistry0104 chemical sciences3. Good healthCrystallographyOctahedron[CHIM.OTHE] Chemical Sciences/OtherChemistry (miscellaneous)Excited statevisual_artvisual_art.visual_art_mediumThermodynamicsMolecular MedicineDensity functional theory[CHIM.OTHE]Chemical Sciences/Other
researchProduct

Additive functionals and push forward measures under Veretennikov's flow

2014

16 pages; In this work, we will be interested in the push forward measure $(\vf_t)_*\gamma$, where $\vf_t$ is defined by the stochastic differential equation \begin{equation*} d\vf_t(x)=dW_t + \ba(\vf_t(x))dt, \quad \vf_0(x)=x\in\mbR^m, \end{equation*} and $\gamma$ is the standard Gaussian measure. We will prove the existence of density under the hypothesis that the divergence $\div(\ba)$ is not a function, but a signed measure belonging to a Kato class; the density will be expressed with help of the additive functional associated to $\div(\ba)$.

[MATH.MATH-PR]Mathematics [math]/Probability [math.PR]010104 statistics & probability[MATH.MATH-PR] Mathematics [math]/Probability [math.PR]010102 general mathematicsstochastic flowsAdditive functionalsmeasures in Kato class0101 mathematics01 natural sciencesAMS 2000 subject classifications. Primary 60H10; secondary 60J35 60J60.[ MATH.MATH-PR ] Mathematics [math]/Probability [math.PR]
researchProduct

A Hirshfeld partitioning of polarizabilities of water clusters

2006

International audience; A new Hirshfeld partitioning of cluster polarizability into intrinsic polarizabilities and charge delocalization contributions is presented. For water clusters, density-functional theory calculations demonstrate that the total polarizability of a water molecule in a cluster depends upon the number and type of hydrogen bonds the molecule makes with its neighbors. The intrinsic contribution to the molecular polarizability is transferable between water molecules displaying the same H-bond scheme in clusters of different sizes, and geometries, while the charge delocalization contribution also depends on the cluster size. These results could be used to improve the existin…

[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]010304 chemical physicsChemistryHydrogen bondGeneral Physics and AstronomyCharge (physics)010402 general chemistry01 natural sciences0104 chemical sciencesDelocalized electron[ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]PolarizabilityChemical physics0103 physical sciencesCluster sizeCluster (physics)Physics::Atomic and Molecular ClustersMoleculeDensity functional theoryPhysics::Atomic PhysicsPhysical and Theoretical ChemistryAtomic physicsPhysics::Chemical Physics
researchProduct

Symmetry breakings in a metal organic framework with a confined guest

2020

The MOF $[{\text{Fe(tvp)}}_{2}{(\text{NCS})}_{2}]\ifmmode\cdot\else\textperiodcentered\fi{}2\text{BzCHO}$ is demonstrated to undergo a complex sequence of phase transitions and spin-crossover behavior of its constitutive ${\text{Fe}}^{\text{II}}$ ions upon adsorption of benzaldehyde guest molecules. Our study, combining Raman and synchrotron x-ray diffraction measurements on a single crystal, reveals that the conversion from the pure high-spin to the pure low-spin phases implies a rich sequence of intermediate phases, with symmetry breaking forming at least three different space groups. These different symmetries involve spin-state ordering, ligand ordering, and guest ordering, interpreted …

[PHYS]Physics [physics]PhysicsPhase transitionSpace group02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesMagnetic susceptibilityCrystallographysymbols.namesake0103 physical sciencessymbols[CHIM]Chemical SciencesMoleculeDensity functional theorySymmetry breaking010306 general physics0210 nano-technologyRaman spectroscopySingle crystalPhysical Review B
researchProduct