Question

What is molecular polarisability explain different types of polarisability?

Answer 1

Polarizability is the ability to form instantaneous dipoles. It is a property of matter. Polarizabilities determine the dynamical response of a bound system to external fields, and provide insight into a molecule's internal structure.

Electric polarizability

Electric polarizability is the relative tendency of a charge distribution, like the electron cloudof an atom or molecule, and consequently of any material body, to have its charges displaced by any external electric field, which in the uniform case is applied typically by a charged parallel-plate capacitor.

Magnetic polarizability

Magnetic polarizability defined by spininteractions of nucleons is an important parameter of deuterons and hadrons. In particular, measurement of tensorpolarizabilities of nucleons yields important information about spin-dependent nuclear forces.[9]

Answer 2

Answer:

The polarizability of an atom or molecule is defined as the ratio of its induced dipole moment to the local electric field; in a crystalline solid, one considers the dipole moment per unit cell

Different types of polarisability

• Electronic polarization: refers to the separation of center of positive charge and the center of negative charge in a material. The separation can be caused by a sufficiently high-electric field.
• Ionic polarization: occurs due to relative displacements between positive and negative ions in an ionic crystal. If a crystal or molecule consists of atoms of more than one kind, the distribution of charges around an atom in the crystal or molecule leans to positive or negative
• Orientation polarization: in the absence of external electric field electric dipoles are so oriented randomly that their net effect becomes zero but in presence of electric field, these dipole try to rotate and align in the direction of electric field.
• Total Electric polarization:  refers to the separation of center of positive charge and the center of negative charge in a material. The separation can be caused by a sufficiently high-electric field.