van der Waals force

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van der Waals force

[′van dər ‚wȯlz ‚fȯrs]
(physical chemistry)
An attractive force between two atoms or nonpolar molecules, which arises because a fluctuating dipole moment in one molecule induces a dipole moment in the other, and the two dipole moments then interact. Also known as dispersion force; London dispersion force; van der Waals attraction.
References in periodicals archive ?
Although the literature on economic geography and urban economics dates back at least to the work of Alfred Marshall in the late 19th century, separating agglomeration and dispersion forces from variation in location fundamentals remains challenging.
From an empirical perspective, the challenge is to find exogenous sources of variation in the surrounding concentration of economic activity to help disentangle agglomeration and dispersion forces from variation in location fundamentals.
Also, the van der Waals dispersion forces contribute significantly to the adsorption energy.
In addition to the hydrogen bonds, van der Waals dispersion forces are present during the cellulose-water interactions.
Pulling in the opposite direction are dispersion forces: product market competition (meaning that some firms remain dispersed in order to supply remote consumers) and high urban prices of immobile factors.
This is because when trade in goods is expensive, supply and demand in each country's product market (one of the dispersion forces of Section II) are the dominant forces which determine the location of activity.
Thus, the work of adhesion arises only from the dispersion forces. On the other hand, Cloisite 30B has two hydroxyl groups per molecule of organic modifier, which can form hydrogen bonds with the polyamide matrix.
The cellulose chains are arranged in a parallel manner and are organized in sheets stabilized by interchain OH-O hydrogen bonds, whereas the stacking of the sheets is stabilized by both vdW dispersion forces and weak CH-O hydrogen bonds [13, 14] (Figures 6 and 7).
Dispersive component refers to London dispersion forces, and specific interactions refer to the polar, ionic, electrical, metallic, and acid-base interactions.
This is due to the size of chlorine atom that is bigger than that of fluorine, thus exerting a significant impact on the London dispersion force and also the lipophilicity [17, 18].