TLS Online TPP Program

#Id: 8260

#Unit 1. Molecules and their Interaction Relevant to Biology

When an instantaneous dipole atom approaches a neighbouring atom, it can cause that atom to also produce dipoles.

The neighbouring atom is then considered to have an induced dipole moment.

TLS Online TPP Program

#Id: 8261

#Unit 1. Molecules and their Interaction Relevant to Biology

The potential energy of the dipole-induced dipole interaction is:

α = polarizability of the nonpolar molecule

TLS Online TPP Program

#Id: 8262

#Unit 1. Molecules and their Interaction Relevant to Biology

Even though these two atoms are interacting with each other, their dipoles may still fluctuate. However, they must fluctuate in synchrony in order to maintain their dipoles and stay interacted with each other. Result of synchronizing fluctuation of dipoles:

TLS Online TPP Program

#Id: 8263

#Unit 1. Molecules and their Interaction Relevant to Biology

Spontaneous Dipole-Induced Dipole Interaction

Spontaneous dipole-induced dipole interactions are also known as dispersion or London forces

TLS Online TPP Program

#Id: 8264

#Unit 1. Molecules and their Interaction Relevant to Biology

Dispersion or London forces are large networks of intermolecular forces between nonpolar and non-charged molecules and atoms (i.e. alkanes, noble gases, and halogens). 

TLS Online TPP Program

#Id: 8265

#Unit 1. Molecules and their Interaction Relevant to Biology

Molecules that have induced dipoles may also induce neighbouring molecules to have dipole moments, so a large network of induced dipole-induced dipole interactions may exist.