Constant-volume heat capacity at glass transition

Abstract We analyze the jump of heat capacity at glass transition, and calculate the constant-volume heat capacity change Δ C v at glass transition in the common glass formers. The experimental heat capacity jump Δ C p includes both dynamic and dilation’s contributions. The Δ C v removes the dilation’s contribution, and only refers to the dynamic contribution. We find that the ratio Δ C v /Δ C p does not change with the liquid fragility, and almost keeps a constant: 0.85. The results might have implications for a fundamental understanding to the nature of glass transition.