Results 211 to 220 of about 136,748 (262)

Linear free energy relationships and solvolysis reactions

Tetrahedron, 1977
Abstract The validity of Grunwald-Winstein m values in relation to mechanistic designation of solvolysis reactions is examined. Stability-selectivity relationships in this area are shown to form examples of LFER's and not to emanate from correlations between selectivity and reactivity.
I. Roberts, C.D. Johnson, P.G. Taylor
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A hyperbolic modification of linear free energy relationships

Journal of the Chemical Society, Perkin Transactions 2, 1981
In a one-step reaction the activation energies in either forward or reverse reactions cannot be negative. This limitation specifically excludes very wide-range linear dependences of Ea upon ΔH. Analogously, all rate constants have upper limits (in addition to the diffusion limit), and thus linear free energy relationships such as the Hammett or ...
Edward S. Lewis, Celia C. Shen, Rory A. More O'Ferrall   +2 more
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Linear free-energy relationship

Chemical Physics Letters, 2006
Abstract It is shown that a nature of the LFER phenomenon is related to phase volumes of the system’s states, for which a difference of free energy is determined. An invariability of these volumes is the single factor generating the LFER phenomenon.
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Linear Free Energy Relationships in Chemistry of Solutions

ChemInform, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
R. G. Makitra, A. A. Turovsky, G. E. Zaikov   +2 more
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Linear Free Energy Relationship in Ion Thermochemistry

The Journal of Physical Chemistry A, 1997
We report a linear correlation between the proton affinity of 4-substituted pyridines and the hydride affinity of comparably substituted methyl cations that spans almost 30 and 120 kcal/mol, respec...
Dana A. Shea, Ruud J. J. M. Steenvoorden, Peter Chen   +2 more
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Establishing linear-free-energy relationships for the quadricyclane-to-norbornadiene reaction

Organic & Biomolecular Chemistry, 2020
The kinetics of the thermal quadricyclane-to-norbornadiene (QC-to-NBD) isomerization follows a linear-free-energy relationship when using Creary radical values for a selection of aryl/cyano disubstituted derivatives.
Mads Mansø, Anne Ugleholdt Petersen, Kasper Moth-Poulsen, Mogens Brøndsted Nielsen   +3 more
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Linear Free Energy Relationships and Optical Spectroscopy

1972
In this chapter we aim to provide a general indication of the present situation in the correlation of the frequencies and intensities of absorption bands with substituent effects. We have made no attempt to include all the extant references to this subject. Since 1947 many authors have compared spectral parameters with sigma values; however many of the
A. R. Katritzky, R. D. Topsom
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The isokinetic relationship. IX. Connections to linear free energy relationships

Chemical Physics, 1988
Abstract The mutual interrelations between common points of intersection in various temperature-dependent linear free-energy relationships (LFERs) are analysed and compared with experimental examples. With this approach isoparametric and isokinetic relationships are brought under the umbrella of one treatment.
Wolfgang Linert, Valentin N. Sapunov
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Advances in Linear Free Energy Relationships

1972
1 The Hammett Equation-the Present Position.- 2 The Separation of Polar, Steric, and Resonance Effects by the Use of Linear Free Energy Relationships.- 3 Linear Free Energy Relationships and Optical Spectroscopy.- 4 Linear Correlations of Substituent Effects in 1H, 19F, and 13C Nuclear Magnetic Resonance Spectroscopy.- 5 The Influence of the Solvent on
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Linear Free Energy Relationship for Actinide Sorption to Graphene Oxide

ACS Applied Materials & Interfaces, 2018
Th(IV) and Np(V) sorption to graphene oxide (GO) was studied as a function of pH from 0-7.5 and analyte concentrations (0.01-1 mg/L for Th(IV) at pH 3 and 0.005-10 mg/L for Np(V) at pH 7). Starting at pH 1, greater than 90% Th(IV) sorption to GO occurred while significant Np(V) sorption to GO started at pH 5.
Yu Xie, Brian A. Powell
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