Transcript van der Waals force

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The van der Waals equation is an
equation of state that can be derived from
a special form of the potential between a
pair of molecules (hard-sphere repulsion
and R-6 van der Waals attraction).
In physical chemistry, the van der Waals
force (or van der Waals interaction),
named after Dutch scientist Johannes Diderik
van der Waals, is the attractive or repulsive
force between molecules (or between parts
of the same molecule) other than those due
to covalent bonds or to the electrostatic
interaction of ions with one another or with
neutral molecules.[1]
The term includes:
1. permanent dipole–permanent dipole forces
2. permanent dipole–induced dipole forces
3. instantaneous induced dipole-induced dipole
(London dispersion forces)
It is also sometimes used loosely as a synonym
for the totality of intermolecular forces. Van
der Waals forces are relatively weak
compared to normal chemical bonds, but play
a fundamental role in fields as diverse as
supramolecular chemistry, structural biology,
polymer science, nanotechnology, surface
science, and condensed matter physics.
Van der Waals forces define the chemical
character of many organic compounds. They
also define the solubility of organic
substances in polar and non-polar media. In
low alcohols, the properties of the polar
hydroxyl group dominate the weak
intermolecular forces of van der Waals. In
higher alcohols, the properties of the unpolar
alkyl rest (R) dominate and define the
solubility. Van der Waals forces grow with the
length of the non polar part of the
substance.