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The "explanation" of the dispersion force as the interaction between two such dipoles was invented after London arrived at the proper quantum mechanical theory. The authoritative work [ 13 ] contains a criticism of the instantaneous dipole model [ 14 ] and a modern and thorough exposition of the theory of intermolecular forces.
Dispersion (usually named London dispersion interactions after Fritz London), which is the attractive interaction between any pair of molecules, including non-polar atoms, arising from the interactions of instantaneous multipoles. When to apply the term "van der Waals" force depends on the text.
Dispersion forces keep the molecule inert even while its core Si-Si bond lengthens. Similarly, the longest known Ge-Ge bond is found in t Bu 3 GeGe t Bu 3 and is also facilitated by dispersion stabilization. [19] Dispersion stabilization has also been invoked for (t BuC) 3 P, a main group analog of a hydrocarbon tetrahedrane. [20]
The dispersion (London) force is the most important component because all materials are polarizable, whereas Keesom and Debye forces require permanent dipoles. The London interaction is universal and is present in atom-atom interactions as well. For various reasons, London interactions (dispersion) have been considered relevant for interactions ...
The source of adhesive forces, according to the dispersive adhesion mechanism, is the weak interactions that occur between molecules close together. [2] These interactions include London dispersion forces, Keesom forces, Debye forces and hydrogen bonds. Individually, these attractions are not very strong, but when summed over the bulk of a ...
Hexane is a good example of a molecule with no polarity or highly electronegative atoms, yet is a liquid at room temperature due mainly to London dispersion forces. In this example, when one hexane molecule approaches another, a temporary, weak partially negative dipole on the incoming hexane can polarize the electron cloud of another, causing ...
Forces stronger than London dispersion forces that are also van der Waals include Debye forces, Keesom forces, hydrogen bonds, ionic bonds and induced ion forces; see intermolecular force. The "London forces" are dominant in nonpolar molecules that do not have the stronger forces, as they lack permanent dipoles, and increase in strength given ...
In condensed matter physics and physical chemistry, the Lifshitz theory of van der Waals forces, sometimes called the macroscopic theory of van der Waals forces, is a method proposed by Evgeny Mikhailovich Lifshitz in 1954 for treating van der Waals forces between bodies which does not assume pairwise additivity of the individual intermolecular forces; that is to say, the theory takes into ...