Gibbs energy change via temperature change and electric displacement change

The infinitesimal change in Gibbs energy of a system with a dielectric medium can be expressed using the change in temperature and the change in electric field strength.

Conditions:

  1. The dielectric is isotropic whether or not the electric field is present.

  2. The medium is homogeneous.

  3. The volume change of the medium is insignificant.

Links:

  1. Formula 31.8 on p. 122 of “General Course of Physics” (Obschiy kurs fiziki), vol. 3 by Sivukhin D.V. (1979).

gibbs_energy_density_change

Infinitesimal change in gibbs_energy of the system per unit volume.

Symbol:

dG

Latex:

\(dG\)

Dimension:

energy/volume

entropy_density

entropy of the system per unit volume.

Symbol:

S

Latex:

\(S\)

Dimension:

energy/(temperature*volume)

temperature_change

Infinitesimal change in temperature of the system.

Symbol:

dT

Latex:

\(dT\)

Dimension:

temperature

electric_displacement

electric_displacement.

Symbol:

D

Latex:

\(D\)

Dimension:

charge/area

electric_field_change

Infinitesimal change in electric_field_strength.

Symbol:

dE

Latex:

\(dE\)

Dimension:

voltage/length

law

dG = -S * dT - D * dE

Latex:
\[dG = - S dT - D dE\]