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Leakage in chemistry

Definitions

• Electric polarisability : relative tendency of a charge distribution, like the electron cloud of an atom or molecule, to be distorted from its normal shape by an external electric field, measured a the quotient of the induced dipole moment over the electric field strength $\alpha ={\displaystyle \frac{|p|}{|E|}}$

Leakage in electronics

• Leakage is the gradual transfer of electrical energy across a boundary normally viewed as insulating, such as the spontaneous discharge of a charged capacitor or magnetic coupling of a transformer with other components

Leakage in electrohydrodynamics

• perfect conductors : mercury or water
• perfect dielectrics : apolar liquids such as benzene that are excellent insulators
• poorly conducting liquids = leaky dielectrics

Regular dielectrics

• no loosely bound, or free, electrons that may drift through the material under an electric field
• instead electrons slightly shift from their average equilibrium positions, causing dielectric polarisation

Notes

• Electrokinetics, deals with the behaviour of charged particles in aqueous electrolytes (Saville 1977, Russel et al 1989)
• There are significant differences between the behaviour of electrolytes and leaky dielectrics