Dipole interact ion

The main conclusion from the above measurements is that a critical step in photodegradation is adsorption of the organic substrate on the surface. Therefore the parameters that control photodegradation are directly related to the parameters that govern adsorption processes, and include van der Waals forces, dipole-dipole interaction, ion-exchange, hydrogen bonding, hydrophobic interactions, n-n interactions, and donor-acceptor interactions. 

Dipole interact ions,. tee Electrostatic forces Dispersion forces (energies), 44-47 on alumina, 245 in gas-solid adsorption, 243-245 Displacement chromatography, 34-36 Distribution coefficient A, lOi-ll calculation (examples), 385-396 correlation between different adsorbent batches, 148-149... 

The structure of repeat units of individual polymers constituting a blend and the nature of interactions between polymers in a blend are the factors that influence solubility characteristics of a blend. Thus, soluMlity is affected by cross-linking, hydrogen bonding, formation of donor-acceptor complexes, dipole-dipole interactions, ion-dipole interactions, ion-ion interactions, and segmental interactions. 

There are two types of ion-dipole interactions ion—dipole bonds and dative covalent bonds. 

Hydrophobic Immunoassay Immtmogen Immtmological reaction Ion-dipole interactions Ion-ion interactions Ionization center Isoelectric point (isoelectric pH)... 

FIGURE 12.8 Ion-Dipole Interactions Ion-dipole interactions such as those between potassium ions, fluoride ions, and water molecules cause the heat of hydration to be largely negative (exothermic). 

As we discovered in Chapter 11, molecules have dipole moments because of electronegativity differences between atoms. The dipole moment in a molecule will interact with a charged ion to form an ion-dipole interaction. Ion-dipole interactions are important in understanding the dissolution of salts. 

If the molecule is an ion bearing a charge 2, then the leading induction tenn is the isotropic, charge-indiiced-dipole interaction... 

This fomuila does not include the charge-dipole interaction between reactants A and B. The correlation between measured rate constants in different solvents and their dielectric parameters in general is of a similar quality as illustrated for neutral reactants. This is not, however, due to the approximate nature of the Bom model itself which, in spite of its simplicity, leads to remarkably accurate values of ion solvation energies, if the ionic radii can be reliably estimated [15],... 

The polarization interaction arises from the interaction between the ion of charge Ze and the multipole moments it induces in the atom or molecule AB. The dominant polarization interaction is the ion-mduced dipole interaction... 

Ion-Dipole Forces. Ion-dipole forces bring about solubihty resulting from the interaction of the dye ion with polar water molecules. The ions, in both dye and fiber, are therefore surrounded by bound water molecules that behave differently from the rest of the water molecules. If when the dye and fiber come together some of these bound water molecules are released, there is an increase in the entropy of the system. This lowers the free energy and chemical potential and thus acts as a driving force to dye absorption. 

The attractions between the water molecules interacting with, or hydrating, ions are much greater than the tendency of oppositely charged ions to attract one another. The ability of water to surround ions in dipole interactions and... 

The favorability of acid-base reactions is affected, in pa by electrostatic interactions between charged atoms a dipoles within the same molecule. The equilibrium w shift in the direction of an ion that is stabilized 1 intramolecular ion-dipole interactions. 

Decide if ion-dipole interactions are responsible for the observed substituent effects. Obtain the charge on carbon and nitrogen in each cyano group. What evidence is there for a polar CN bond Should the ion (O )-dipole (CN) interaction be stabilizing or destabilizing Can these interactions explain the trends in electrostatic potential (Hint Focus on changes in O—CN distance and in orientation of the cyano group.)... 

Ion-dipole interactions interact over longer distances. Their mean interaction energy 0id decreases with r-4 3) ... 

Hydrophilic hydration signifies that a strong energetically favored direct interaction exists between dissolved polar or ionic particle and the surrounding water molecules by ion-dipole-, dipole-dipole-interactions and/or hydrogen bonds. 

In this review, recent development of active transport of ions accross the liquid membranes using the synthetic ionophores such as crown ethers and other acyclic ligands, which selectively complex with cations based on the ion-dipole interaction, was surveyed,... 

Ionophores constitute a large collection of structurally diverse substances that share the ability to complex cations and to assist in the translocation of cations through a lipophilic interface.1 Using numerous Lewis-basic heteroatoms, an ionophore organizes itself around a cationic species such as an inorganic metal ion. This arrangement maximizes favorable ion-dipole interactions, while simultaneously exposing a relatively hydrophobic (lipophilic) exterior. 

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