An iterative semi-implicit scheme with robust damping
, 2008 An efficient, iterative semi-implicit (SI) numerical method for the time integration of stiff wave systems is presented. Physics-based assumptions are used to derive a convergent iterative formulation of the SI scheme which enables the monitoring and ...
Ascher +51 more
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Theoretical estimation of Hammett σ p constants of organic radical groups
Chinese Science Bulletin, 2010 A quantum chemistry method was developed to calculate the Hammett substituent constants of various organic radicals. These newly obtained constants allow, for the first time, the quantitative analysis of the electron demand of organic radicals. Calculations reveal that the electron demand of organic radicals varies dramatically.
Chen Wang, Yao Fu, Lei Liu
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ChemistryThis study presents a quantitative investigation of substituent effects on the stability of 1:2 complexes formed between para-substituted 2-phenylbenzimidazole ligands and Cu(II) or Co(II) ions.
Zoltán Köntös +2 more
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The Electrochemical Oxidation of Substituted Catechols [PDF]
, 1980 The oxidation of substituted catechols was studied by cyclic voltammetry, chronoamperometry, rotating ring‐disk electrode, and coulometry. The results showed that the quinones that were formed from the oxidation of substituted catechols reacted with the ...
Chen, Wen-Yu +2 more
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Macedonian Journal of Chemistry and Chemical Engineering, 2015 The protonation of ten aliphatic amides in sulfuric acid media was studied by UV spectroscopy. The pKBH+ values and solvation parameters were calculated using Yates and McClelland Method, Excess Acidity Method and Bunnett and Olsen Method.
Goran Stojković +2 more
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Trivial Meet and Join within the Lattice of Monotone Triangles [PDF]
, 2014 The lattice of monotone triangles $(\mathfrak{M}_n,\le)$ ordered by entry-wise comparisons is studied. Let $\tau_{\min}$ denote the unique minimal element in this lattice, and $\tau_{\max}$ the unique maximum.
Engbers, John, Hammett, Adam
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von K\'arm\'an energy decay and heating of protons and electrons in a kinetic turbulent plasma
, 2013 Decay in time of undriven weakly collisional kinetic plasma turbulence in systems large compared to the ion kinetic scales is investigated using fully electromagnetic particle-in-cell simulations initiated with transverse flow and magnetic disturbances ...
Matthaeus, W. H. +4 more
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Extending the semi-empirical PM6 method for carbon oxyacid pKa prediction to sulfonic acids: Application towards congener-specific estimates for the environmentally and toxicologically relevant C1 through C8 perfluoroalkyl derivatives [PDF]
, 2009 A positive bias in the semi-empirical PM6 method for estimating pKa values of sulfonic acids was corrected by a correlation developed between non-adjusted PM6 pKa values and the corresponding experimentally obtained/estimated acidity constants for a ...
Kaya Forest +2 more
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Unraveling substituent effects on frontier orbitals of conjugated molecules using an absolutely localized molecular orbital based analysis. [PDF]
, 2018 It is common to introduce electron-donating or electron-withdrawing substituent groups into functional conjugated molecules (such as dyes) to tune their electronic structure properties (such as frontier orbital energy levels) and photophysical properties
HEAD-GORDON, Martin +2 more
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A Perspective Distilled from Seventy Years of Research [PDF]
, 2009 Physical organic chemistry might be regarded as officially recognized as a distinct discipline through the publication of L. P. Hammett’s book of that title, although substantial earlier work can be traced back to the turn of the 20th century.
Roberts, John D.
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