Search results for "parr"

showing 10 items of 211 documents

New fitting scheme to obtain effective potential from Car-Parrinello molecular dynamics simulations: Application to silica

2008

A fitting scheme is proposed to obtain effective potentials from Car-Parrinello molecular dynamics (CPMD) simulations. It is used to parameterize a new pair potential for silica. MD simulations with this new potential are done to determine structural and dynamic properties and to compare these properties to those obtained from CPMD and a MD simulation using the so-called BKS potential. The new potential reproduces accurately the liquid structure generated by the CPMD trajectories, the experimental activation energies for the self-diffusion constants and the experimental density of amorphous silica. Also lattice parameters and elastic constants of alpha-quartz are well-reproduced, showing th…

Car–Parrinello molecular dynamicsMaterials sciencemolecular dynamics calculations (Car-Parrinello) and other numerical simulationsTransferabilityGeneral Physics and AstronomyFOS: Physical sciences02 engineering and technologyglasses01 natural sciencesMolecular physicsMolecular dynamicsLattice (order)0103 physical sciences[PHYS.COND.CM-DS-NN]Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn]010306 general physicsdensity functional theoryCondensed Matter - Materials Sciencegradient and other correctionsMaterials Science (cond-mat.mtrl-sci)Disordered Systems and Neural Networks (cond-mat.dis-nn)computer simulation of liquid structureCondensed Matter - Disordered Systems and Neural Networks021001 nanoscience & nanotechnologylocal density approximation[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Amorphous silica0210 nano-technologyPair potential
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Applications of the Conceptual Density Functional Theory Indices to Organic Chemistry Reactivity.

2016

Indexación: Web of Science Theoretical reactivity indices based on the conceptual Density Functional Theory (DFT) have become a powerful tool for the semiquantitative study of organic reactivity. A large number of reactivity indices have been proposed in the literature. Herein, global quantities like the electronic chemical potential μ, the electrophilicity ω and the nucleophilicity N indices, and local condensed indices like the electrophilic and nucleophilic Parr functions, as the most relevant indices for the study of organic reactivity, are discussed. http://www.mdpi.com/1420-3049/21/6/748

Chemical PhenomenaNucleophilicityChemistry OrganicPharmaceutical ScienceElectronsnucleophilicityReview010402 general chemistry01 natural sciencesreactivity indicesAnalytical ChemistryMolecular electron density theorylcsh:QD241-441Reactivity indicesNucleophilelcsh:Organic chemistryconceptual DFTParr functionsComputational chemistryDrug DiscoveryOrganic chemistryReactivity (chemistry)Physical and Theoretical ChemistryElectrophilicity010405 organic chemistryChemistryOrganic Chemistrymolecular electron density theory0104 chemical sciencesChemistry (miscellaneous)Conceptual DFTElectrophileMolecular MedicineQuantum TheoryDensity functional theoryelectrophilicityMolecules (Basel, Switzerland)
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Comparative classical and ab initio Molecular Dynamics study of molten and glassy germanium dioxide

2008

A Molecular Dynamics (MD) study of static and dynamic properties of molten and glassy germanium dioxide is presented. The interactions between the atoms are modelled by the classical pair potential proposed by Oeffner and Elliott (OE) [Oeffner R D and Elliott S R 1998, Phys. Rev. B, 58, 14791]. We compare our results to experiments and previous simulations. In addition, an ab initio method, the so-called Car-Parrinello Molecular Dynamics (CPMD), is applied to check the accuracy of the structural properties, as obtained by the classical MD simulations with the OE potential. As in a similar study for SiO2, the structure predicted by CPMD is only slightly softer than that resulting from the cl…

Condensed Matter - Materials ScienceGermanium dioxideCar–Parrinello molecular dynamicsMaterials scienceDynamic structure factorRelaxation (NMR)Ab initioMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesThermodynamicsDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural NetworksCondensed Matter Physicschemistry.chemical_compoundMolecular dynamicsgermaniamolecular dynamics simulationchemistryAb initio quantum chemistry methodsGeneral Materials SciencePair potential
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A Roof Tile from 1678 Found in Calasparra (Murcia) as an Abiding Medium of Writing

2017

Analysis of a red clay roof tile which bears an heretofore unknown inscription of the late 'procesal' script style and humanistic characters along with the date 1678, marking its exact year of manufacture. This tile was found on the roof of an old barn structure in ruins, located on 'Horno de Calasparra' Street (Murcia), before its demolition. We will also point out some of the more significant aspects of the historic profession of tile making, which has all but disappeared. Se expone a continuación una teja de barro cocido en cuyo lomo se observa incisa una inédita frase, presentando una escritura de tipo procesal tardío, con caracteres ya humanísticos, y una fecha, 1678, la cual marca el …

Cultural StudiesRoof tileHistoryEthnography and Social HistoryWritingmedia_common.quotation_subjectCalasparralcsh:D1-2009PalaeographyArts and Humanities (miscellaneous)MudpaleografíaescrituraHistoria etnográfica y socialmedia_commonlcsh:History (General) and history of EuropebarroArtlcsh:History (General)Roof tilePalaeographyStyle (visual arts)lcsh:Dvisual_artvisual_art.visual_art_mediumcalasparratejaTileBarnHumanitieshistoria etnográfica y socialEl Futuro del Pasado
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Gozos á Santa Ana, madre de María Santísima, que se venera en la Parroquial Iglesia de San Miguel.

El full orlat Il·lustració al·lusiva al goig, amb Santa Anna, la Mare de Déu, Sant Josep, l'Espirit Sant, ángels, etc Text del goig a tres col. separades per bandes

Devocions populars Balears PalmaEsglésia parroquial de Sant Miquel (Palma de Mallorca)Anna Santa Goigs
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Gozos al beato Josef Oriol presbitero y beneficiado de la Iglesia Parroquial de Nra. Sra. del Pino de la Ciudad de Barcelona.

El full orlat Grav. xil. enmarcat del sant, situat entre les paraules del tít. i flanquejat per ornaments florals Text del goig a tres col. separades per filets

Devocions populars Catalunya BarcelonaEsglésia Parroquial de Santa Maria del Pi (Barcelona)Josep Oriol Sant Goigs
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Gozos a los gloriosos S. Valero Obispo, y S. Vicente Martyr, venerados en la Iglesia Parroquial de Ruzafa.

El full orlat Grav. xil. enmarcat dels sants, flanquejat per gerros amb flors Text del goig a tres col. separades per filets Les primeres lletres de cada estrofa formen les paraules VALERO i VICENTE

Devocions populars Comunitat Valenciana Obres anteriors al 1800Església Parroquial de Sant Valero i Sant Vicent Màrtir (Russafa València) Obres anteriors al 1800 lemacValero Sant Goigs Obres anteriors al 1800 lemacVicent màrtir Sant Goigs Obres anteriors al 1800 lemac
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Gozos al glorioso San Gil Abad, venerado en la Parroquial de San Lorenzo.

El full orlat. Grav. xil. enmarcat del sant, flanquejat per gerros amb flors. Text del goig a dues col. separades per banda.

Devocions populars Comunitat Valenciana.Església parroquial de Sant Llorenç (València)Egidi sant Goigs.
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Gozos al glorioso San Gil Abad : Venerado en la Parroquial del invicto Mártir San Lorenzo.

El full orlat. Grav. xil. enmarcat del sant, flanquejat per gerros amb flors. Text del goig a dues col. separades per banda.

Devocions populars Comunitat Valenciana.Església parroquial de Sant Llorenç (València)Egidi sant Goigs.
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Gozos al glorioso San Gil Abad, venerado en la Parroquial del Glorioso Martir San Lorenzo.

El full orlat. Grav. xil. enmarcat del sant, flanquejat per gerros amb flors. Text del goig a dues col. separades per banda.

Devocions populars Comunitat Valenciana.Església parroquial de Sant Llorenç (València)Egidi sant Goigs.
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