van der Waals forces


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van der Waals forc·es

(von der vahls),
first postulated by van der Waals in 1873 to explain deviations from ideal gas behavior seen in real gases; the attractive forces between atoms or molecules other than electrostatic (ionic), covalent (sharing of electrons), or hydrogen bonding (sharing a proton); generally ascribed to dipolar and dispersion effects, π-electrons, and the like; these relatively nondescript forces contribute to the mutual attraction of organic molecules.

van der Waals forc·es

(vahn der valz fōrs'ĕz)
Attractions first postulated by J.D. van der Waals in 1873 to explain deviations from ideal gas behavior seen in real gases; the attractive forces between atoms or molecules other than electrostatic (ionic), covalent (sharing of electrons), or hydrogen bonding (sharing a proton); generally ascribed to dipolar and dispersion effects, π-electrons, and other factors; these relatively nondescript forces contribute to the mutual attraction of organic molecules.

van der Waals forces

Weak attractions between non-polar parts of molecules. (Johannes D. van der Waals, Dutch physicist and Nobel laureate, 1837–1923).

van der Waals,

Johannes D., Dutch physicist and Nobel laureate, 1837-1923.
van der Waals forces - explains deviations from ideal gas behavior seen in real gases. Synonym(s): London forces
References in periodicals archive ?
One is the attractive van der Waals force at the CNT/Au interface before EBID.
Electrical engineer Ronald Fearing of the University of California, Berkeley, who studies geckos, agrees that van der Waals forces must still play a role.
On the other hand, the van der Waals forces have been taken into account in [34], where an approximate Rayleigh-Ritz method has been adopted, using a single-term trial function.
3(b) the curve 1 shows the change of the potential energy of surface atoms under van der Waals forces. At the point [R.sub.1] potential energy reaches minimum, and the cohesion strength of two crystals is determined by energy [E.sub.1] with relatively small value, not more than 1kJ/mol.
1) The resolution of an evolution equation for the interface film establisbed within the lubrication approximation and taking into account the migration of surfactant molecules, but neglecting the effect of microscopic molecular collisions and van der Waals forces, has allowed the description of the dynamics exhibited by the interface film in this simplified case.
Elastic moduli of multi-walled carbon nanotubes and the effect of van der Waals forces. Composites Sci.
Maugis (48) gives an account of van der Waals forces between solids.
As the PPs are in a perpetual state of ZP agitation about their average "r" positions, however, there is a residual, random van der Waals force that the two PPs, and hence the PV as a whole, exert on the free mass.
Numerical values of these energies show strength of van der Waals forces and results are summarized in Tables 5 and 6.
Weak attractions between the AFM tip and bitumen were sometimes observed at separations less than 5 nm as a result of attractive van der Waals forces; the Hamaker constant for the bitumen-water-silicon nitride system is [A.sub.123] = 2.7 x [10.sup.-20] J.
The material mimics the pads on the bottoms of gecko feet, from which microscopic hairs protrude; as the pad touches a surface, the hairs employ Van Der Waals forces to create a large, but reversible bond.
It's all down to van der Waals forces, but you knew that.