Search results for "Karplus"

showing 2 items of 2 documents

Karplus-Type Dependence of Vicinal119Sn-13C and119Sn-1H Spin-Spin Couplings in Organotin(IV) Derivatives: A DFT Study

2009

The empirical Karplus-type dependence of (3)J((119)Sn,(13)C) and (3)J((119)Sn,(1)H) couplings in organotin(IV) derivatives has been computationally validated by DFT methods both at the nonrelativistic and scalar ZORA relativistic level. A preliminary calibration of the computational protocols, by comparing experimental and calculated couplings for a Set Of Suitable rigid molecules, revealed their high predictive power: in particular, relativistic results for (3)J((119)Sn,(13)C) have a mean absolute error of just above 2 Hz, over a range of values up to about 70 Hz. The latter protocol has then been used to study in detail the influence of substituents and multiple paths connecting the coupl…

Coupling constantChemistryKarplus equationOrganic ChemistryCarbon-13Scalar (mathematics)Relativistic effectsNuclear magnetic resonance spectroscopyRelativistic effects DFT NMR spectroscopy tinMolecular physicsDensity functional calculations; NMR spectroscopy; Relativistic effects; TinDensity functional calculationsNMR spectroscopyNuclear magnetic resonanceTinMoleculePhysical and Theoretical ChemistryRelativistic quantum chemistryorganotinVicinalSpin-½European Journal of Organic Chemistry
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A DFT study of the vicinal 3J(119Sn,13C) and 3J(119Sn,1H) coupling constants in trimethyl- and chlorodimethyl-stannyl propanoates.

2013

Abstract We have tested the performance of DFT protocols, both at the Scalar relativistic ZORA and non-relativistic level of theory, for the calculation of the 3 J( 119 Sn, 13 C) and 3 J( 119 Sn, 1 H) vicinal couplings for a series of flexible organotin(IV) derivatives with formula XMe2SnCHRCHR′COOMe (X = Me, Cl; R, R′ = Me, Ph). A satisfactory agreement between experimental and calculated vicinal couplings has been obtained by taking into account the conformational behaviour of the compounds investigated. The protocols used, mainly the relativistic one, were found to give a correct picture of the populations and a sufficiently high overall performance in calculating the vicinal couplings, …

Coupling constantheteronuclear NMR spectroscopySeries (mathematics)ChemistryOrganoTin(IV) 119Sn NMR 119Sn couplings Karplus DFT Relativistic ZORAOrganic ChemistryScalar (mathematics)heteronuclear NMR spectroscopy; DFT calculations; tin compoundstin compoundsDFT calculationsBiochemistryInorganic ChemistryComputational chemistrySettore CHIM/03 - Chimica Generale E InorganicaMaterials ChemistryOverall performancePhysical and Theoretical ChemistryVicinal
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