ðə ɡɹˈænd pətˈɛnʃəl ɔːɹ lˈændaʊ pətˈɛnʃəl ɔːɹ lˈændaʊ fɹˈiː ˈɛnɚdʒi ɪz ɐ kwˈɔntᵻɾi jˈuːzd ɪn stɐtˈɪstɪkəl mᵻkˈænɪks, ɪspˈɛʃəli fɔːɹ ɪɹᵻvˈɜːsᵻbəl pɹˈɑːsɛsᵻz ɪn ˈoʊpən sˈɪstəmz.
The grand potential or Landau potential or Landau free energy is a quantity used in statistical mechanics, especially for irreversible processes in open systems.