Polarisation definition in chemistry

Polarisation in chemistry refers to the distortion of the electron cloud of a molecule, atom, or ion when it is subjected to an electric field. This distortion leads to a change in the distribution of the electron cloud, causing one side to become more negatively charged and the other more positively charged. This phenomenon is known as polarisation.

Here are the steps to understand it:

1. Consider a molecule, atom, or ion with a certain distribution of its electron cloud. This distribution is usually symmetrical in the absence of any external influence.

2. When an electric field is applied, the electron cloud of the molecule, atom, or ion is distorted. This means that the electrons, being negatively charged, are attracted towards the positive side of the electric field.

3. This movement of electrons causes a change in the distribution of the electron cloud. One side of the molecule, atom, or ion becomes more negatively charged, while the other side becomes more positively charged.

4. This change in charge distribution is what is referred to as polarisation. The degree of polarisation can vary depending on the strength of the electric field and the nature of the molecule, atom, or ion.

5. Polarisation is a key concept in many areas of chemistry, including physical chemistry and quantum chemistry. It plays a crucial role in understanding the behavior of molecules in different chemical reactions and interactions.