Search results for "ISOTOPE"

showing 2 items of 2232 documents

On the ‘expanded local mode’ approach applied to the methane molecule: isotopic substitutions CH3D ←CH4 and CHD3 ←CH4

2014

Operator perturbation theory and the symmetry properties of the axially symmetric XYZ3 (C3v) type molecules are used for the determination of the spectroscopic parameters in the form of functions of structural parameters and parameters of the intramolecular potential function. Several relations between sets of spectroscopic parameters of these molecules are obtained. The ‘expanded local mode’ model and the general isotopic substitution theory are used to estimate the relations between spectroscopic parameters of CH3D and CHD3, on one hand, and with the Td symmetric isotopic species, CH4, on the other hand. Test calculations with the isotopic relations show that even without including prior …

энергетические уровниChemistryOperator (physics)BiophysicsCondensed Matter PhysicsMolecular physicsSymmetry (physics)3. Good healthAb initio quantum chemistry methodsComputational chemistryIntramolecular forceгамильтонианы эффективныеKinetic isotope effectинфракрасные спектрыMoleculeизотопные эффектыPhysical and Theoretical ChemistryPerturbation theoryAxial symmetryMolecular Biologyметан
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Italica (Seville, Spain): use of local marble in Augustan age

2010

This study concerns 51 marble finds made of “Cipollino verde” coming from the ancient city of Italica (north of the modern city of Santiponce, 9 km NW of Seville, Spain), the earliest Roman settlement in Spain, founded in 206 B.C. The aim of this work was to determine their provenance from Greek and Italian quarries or from local quarries worked in the Iberian Peninsula. Thin-section optical microscopy, X-ray powder diffraction, bulk rock chemistry and O, C and Sr stable isotope analyses were carried out. Results were compared with literature data on “Cipollino verde” marbles quarried in southern Euboea (Greece), Apuan Alps (Italy), Almería, Extremoz, Seville (Spain) and Évora (Portugal). T…

“Cipollino verde” marble; mineralogy; petrography; geochemistry; stable isotopes; Italica; Spainarchaeometry; cipollino verde marble; mineralogy; stable isotopes; spain; italica; roman age; clay samples; pottery; viminacium; petrography; cipollino verde" marble; geochemistrySpainstable isotope“Cipollino verde” marblemineralogyItalicaSettore GEO/09 -Georis. Miner.e Appl.Mineral.-Petrogr. per l'Ambi.ed i B.Cult.petrographygeochemistry
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