Definition of Gibbs free energy in US English:

Gibbs free energy


  • A thermodynamic quantity equal to the enthalpy (of a system or process) minus the product of the entropy and the absolute temperature.

    • ‘The change in Gibbs free energy equals the enthalpy change for the reaction minus the product of the absolute temperature and the change in entropy for the reaction.’
    • ‘The sequences of the two proteins vary at only 12 positions, yet only two positions are largely responsible for the observed difference in Gibbs free energy of denaturation.’
    • ‘In an equilibrium situation (ice and water at 0 degrees Celsius, or salt and a saturated brine) the Gibbs free energy of both components is equal, and nothing (no melting, freezing, dissolving etc.) happens.’
    • ‘The amount of mechanical work that can be performed in these states is equal to the change in the Gibbs free energy that occurs in them.’
    • ‘As pressure is a way to modify the Gibbs free energy, pressure allows the exploration of phase transitions and protein substates.’


Named after J. W. Gibbs (see Gibbs, Josiah Willard).