The Quasi-Gaussian Entropy theory (QGE) is a new statistical mechanics theory (Amadei et al., J. Chem. Phys. (1996), 104, 1560-1574), that can be used to predict the physical-chemistry properties of real and simulated systems in a very wide temperature range. A new expression of the Clausius-Clapeyron equation, based on the QGE, for the evaluation of the liquid-vapor equilibrium pressure of pure liquids, was developed [1]. The new equation is able to predict the liquid-vapor equilibrium pressure curve, with high accuracy, over a large temperature range and for different fluids like water, methanol, and mercury.

The same theory was also applied to the prediction of the thermodynamic properties of a simulated Lennard-Jones fluid [2] and ions in solution [3] over a large temperature range.

Finally, we have developed a theoretical model, based on QGE theory, to study the thermodynamics of protein folding. The model is able to reproduce with high accuracy the heat capacity denaturation curve obtained from differential scanning calorimetry measurements of different proteins [4]. A complete description of the theory

In a next blog, I will give a more detailed description of the theoretical method used in these studies.

REFERENCES

1. Amadei, D. Roccatano, M. E. F. Apol, H. J. C. Berendsen, A. Di Nola. Prediction of the liquid-vapor equilibrium pressure using the Quasi-Gaussian entropy theory. J. Chem. Phys., 105, 7022-7025 (1996).
2. Roccatano, A. Amadei, M. E. F. Apol, A. Di Nola, H. J. C. Berendsen. Application of the quasi-Gaussian entropy theory to molecular dynamics simulations of Lennard-Jones fluids. J. Chem. Phys., 109, 6358-6363 (1998).
3. D’Abramo, M. D’Alessandro, A. Di Nola, D. Roccatano, A. Amadei. Characterization of liquid behavior by means of local density fluctuations. J. Mol. Liq., 117, 17-21 (2005).
4. Roccatano, A. Di Nola, A. Amadei. A theoretical model for the folding/unfolding thermodynamics of single-domain proteins, based on the quasi-Gaussian entropy theory. J. Phys. Chem. B, 108, 5756-5762 (2004).