Ionic Dissociation of SiCl
            4
            : Formation of [SiL
            6
            ]Cl
            4
            with L=Dimethylphosphinic Acid

A molecular surface defined as an isosurface of the valence repulsion energy may be hard or soft with respect to probe penetration. As a probe, the helium atom has been chosen. In addition, the Pauli exclusion principle makes the electronic structure change when the probe pushes the molecule (at a fixed positions of its nuclei). This results in a HOMO-LUMO gap dependence on the probe site on the isosurface. A smaller gap at a given probe position reflects a larger reactivity of the site with respect to the ionic dissociation.

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Etude de l'influence de l'ionicité du milieu réactionnel sur les propriétés texturales de gels d'oxyde de titane

Canadian Journal of Chemistry ◽

10.1139/v74-365 ◽

1974 ◽

Vol 52 (13) ◽

pp. 2502-2512 ◽

Cited By ~ 1

Author(s):

Henry Brusset ◽

Henri-Georges Mendelbaum ◽

Chantal Flicoteaux

Keyword(s):

Reaction Medium ◽

Textural Properties ◽

Low Dielectric Constant ◽

Hydrogen Ions ◽

Aqueous Acid ◽

Low Dielectric ◽

Ionic Dissociation ◽

Two Factors ◽

Free Hydrogen ◽

Acid Reaction

A systematic study has been made of the influence of two factors on the synthesis of titanium dioxide gels: (i) the acidity of the reaction medium and (ii) the presence of a solvent. This study demonstrates that, in an aqueous acid medium, the development of textural properties is related to the concentration of free hydrogen ions. The presence in an acid reaction medium of a solvent, such as butanol or benzene, of low dielectric constant, inhibits the development of the structural properties by lowering the ionic dissociation of the acid. Our results provide an explanation for the apparently divergent measurements in the literature.

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Ionic dissociation of hydroxycyclohexadienyl radical: effect on carbon-13 hyperfine splittings

The Journal of Physical Chemistry ◽

10.1021/j100260a030 ◽

1985 ◽

Vol 89 (14) ◽

pp. 3101-3102 ◽

Cited By ~ 5

Author(s):

Michael Lefcourt ◽

Keith P. Madden ◽

Robert H. Schuler

Keyword(s):

Ionic Dissociation ◽

Hyperfine Splittings

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The Ionic Dissociation of Sodium Triphenylmethyl

Journal of the American Chemical Society ◽

10.1021/ja01273a037 ◽

1938 ◽

Vol 60 (6) ◽

pp. 1403-1406 ◽

Cited By ~ 12

Author(s):

Elijah Swift

Keyword(s):

Ionic Dissociation

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Investigating the Effect of Thermoelectric Processing on Ionic Aggregation in Thermoplastic Ionomers

Volume 1: Development and Characterization of Multifunctional Materials; Mechanics and Behavior of Active Materials; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies ◽

10.1115/smasis2017-3953 ◽

2017 ◽

Author(s):

Prasant Vijayaraghavan ◽

Vishnu-Baba Sundaresan

Keyword(s):

Mechanical Properties ◽

Electrostatic Field ◽

Thermal Studies ◽

Effect Of Temperature ◽

Self Healing ◽

Polymer Backbone ◽

Ionic Dissociation ◽

Dissociation Temperature ◽

Aggregate Morphology ◽

Poly Ethylene

Ionomers are a class of polymers which contain a small fraction of charged groups in the polymer backbone. These ionic groups aggregate (termed ionic aggregates) to form temporary cross-links that break apart over the ionic dissociation temperature and re-aggregate on cooling, influencing the mechanical properties of these polymers. In addition to enhanced mechanical properties, some ionomers also exhibit self-healing behavior. The self-healing behavior is a consequence of weakly bonded ionic aggregates breaking apart and re-aggregating after puncture or a ballistic impact. The structure and properties of ionomers have been studied over the last several decades; however, there is a lack of understanding of the influence of an electrostatic field on ionic aggregate morphology. Characterizing the effect of temperature and electric field on the formation and structure of these ionic aggregates will lead to preparation of ionomers with enhanced structural properties. This work focuses on Surlyn 8940 which a poly-ethylene methacryclic acid co-polymer in which a fraction of the carboxylic acid is terminated by sodium. In this work, Surlyn is thermoelectrically processed over its ionic dissociation temperature in the presence of a strong electrostatic field. Thermal studies are performed on the ionomer to study the effect of the thermoelectric processing. It is shown that the application of a thermoelectric field leads to increase in the ionic aggregate order in these materials and reduction in crystal size distribution. Thermal Analysis is performed using a Differential Scanning Calorimeter and the resulting thermogram analysis shows that thermoelectric processing increases the peak temperature and onset temperature of melting by 4 C and 20 C respectively. The peak width at half maximum of the melting endotherm is reduced by 10 C due to thermoelectric processing. This serves as a measure of the increased crystallinity. A parametric study on the effect of field duration and field strength is also performed.

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Ionic dissociation in complexes of iodine with triphenylarsine and triphenylstibine

Canadian Journal of Chemistry ◽

10.1139/v91-091 ◽

1991 ◽

Vol 69 (4) ◽

pp. 606-610 ◽

Cited By ~ 1

Author(s):

Ying Ru Zhang ◽

Ira Solomon ◽

Seymour Aronson

Keyword(s):

Complex Formation ◽

Chemical Nature ◽

Equilibrium Constants ◽

Electrochemical Technique ◽

High Iodine ◽

Ionic Complex ◽

Ionization Mechanisms ◽

Iodine Complex ◽

Ionic Dissociation ◽

Iodine Complexes

An electrochemical technique has been employed to study the ionization of the iodine complexes of (C6H5)3As, (C6H5)3Sb, and pyridine. Several different ionization mechanisms are proposed depending on the chemical nature and concentration of the reactants. A new ionic complex, (C6H5)3MI22+ is postulated for the interaction of iodine with (C6H5)3As and (C6H5)3Sb at high iodine concentrations. Equilibrium constants have been calculated from the emf data for the various ionization steps. Key words: triphenylarsine, triphenylstibine, iodine, complex formation, ionization.

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