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Application of the multi-standard methodology for calculating 1H NMR chemical shifts
(American Chemical Society, 2012-07)
Gauge including atomic orbitals (GIAO)1H NMR chemical shift calculations have been performed for 66 organic compounds at 72 di fferent levels of theory using the multi-standard approach (MSTD) previously developed for 13C ...
Are accurate computations of the 13C' shielding feasible at the DFT level of theory?
(Wiley, 2014-02)
The goal of this study is twofold. First, to investigate the relative influence of the main structural factors affecting the computation of the 13C0 shielding, namely, the conformation of the residue itself and the next ...
Successful combination of computationally inexpensive GIAO 13C NMR calculations and artificial neural network pattern recognition: a new strategy for simple and rapid detection of structural misassignments
(Royal Society of Chemistry, 2013-07)
GIAO NMR chemical shift calculations coupled with trained artificial neural networks (ANNs) have been shown to provide a powerful strategy for simple, rapid and reliable identification of structural misassignments of organic ...
Iodine activation of alcohols: A computational study
(Springer/Plenum Publishers, 2018-06)
A DFT study aimed at unravelling the origin of catalytic activity of iodine in reaction with alcohols is presented. Computed free energies for generation of the O---I complexes from the separated reactants are around 3 ...
A computational (DFT, MP2) and GIAO NMR study of substituent effects in benzenediazonium mono- and dications
(Wiley VCH Verlag, 2011-02-07)
15N and 13C NMR chemical shifts were computed by GIAO-DFT and GIAO-MP2 for a series of p-substituted benzenediazonium mono- and dications in order to probe the electronic effects of the substituents on the diazonium moiety. ...
Calculation of the aortic arch angles from three-dimensional reconstructions of computed tomography scans: Comparison between an automated program and visual assessment
(Pergamon-Elsevier Science Ltd, 2019-11)
Background: The curvature of the aortic arch is associated with the risk of endoleak formation after thoracic endovascular aortic repair (TEVAR). However, the adequate assessment of the angles of the aorta continues to ...
Theoretical models to predict the inhibitory effect of ligands of sphingosine kinase 1 using QTAIM calculations and hydrogen bond dynamic propensity analysis
(Springer, 2018-07)
We report here the results of two theoretical models to predict the inhibitory effect of inhibitors of sphingosine kinase 1 that stand on different computational basis. The active site of SphK1 is a complex system and the ...
A Multi-standard Approach for GIAO 13C NMR Calculations
(American Chemical Society, 2009-12)
The influence of the reference standard employed in the calculation of 13C NMR chemical shifts was investigated over a large variety of known organic compounds, using different quantum chemistrymethods and basis sets. After ...
Exchange interaction between S = 1/2 centers bridged by multiple noncovalent interactions: Contribution of the individual chemical pathways to the magnetic coupling
(Pergamon-Elsevier Science Ltd, 2017-02)
We report EPR and magnetic measurements of diaqua-(pyridine-2,6-dicarboxylato)Copper(II) together with computational calculations. This compound consists of an extended lattice of magnetically equivalent copper(II) ions ...
Exchange interaction between S = 1/2 centers bridged by multiple noncovalent interactions: Contribution of the individual chemical pathways to the magnetic coupling
(Pergamon-Elsevier Science Ltd, 2017-02)
We report EPR and magnetic measurements of diaqua-(pyridine-2,6-dicarboxylato)Copper(II) together with computational calculations. This compound consists of an extended lattice of magnetically equivalent copper(II) ions ...