The Adam–Gibbs model of cooperative relaxation 60 years later: Perspective and improvements

Abstract Since its publication in 1965, the Adam–Gibbs (AG) model of cooperative relaxation has seen wide use as a conceptual framework to understand the glass transition and related phenomena. However, the AG model’s quantitative utility is hindered by unclear definitions for key quantities and a limiting assumption about the thermodynamic nature of the glass transition. In this work, we reapproach the AG model from the perspective of enthalpy landscapes in order to provide solid foundations to this important theory. The kinetic arrest at $${T}_{g}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>T</mml:mi> <mml:mi>g</mml:mi> </mml:msub> </mml:math> is discussed in terms of entropic loss, with special focus on the contribution from transition point entropy. Implications of the updated framework are discussed, along with perspectives on the current and future use of the AG theory. Graphical abstract