[Paper Review] Can Approximate Integral Equation Theories Accurately Predict Solvation Thermodynamics?

Maksim Mišin|arXiv (Cornell University)|Apr 6, 2017

Advanced Thermodynamics and Statistical Mechanics12 references3 citations

TL;DR

This thesis proposes an advanced pressure correction method within integral equation theories to accurately predict solvation thermodynamics across diverse conditions. By rationally extending the pressure correction to address solvation entropy, the model achieves high accuracy in predicting solvation free energies in water at ambient and non-ambient temperatures, for both neutral and ionic solutes, and is transferable to non-aqueous systems.

ABSTRACT

The thesis focuses on the prediction of solvation thermodynamics using integral equation theories. Our main goal is to improve the approach using a rational correction. We achieve it by extending recently introduced pressure correction, and rationalizing it in the context of solvation entropy. The improved model (to which we refer as advanced pressure correction) is rather universal. It can accurately predict solvation free energies in water at both ambient and non-ambient temperatures, is capable of addressing ionic solutes and salt solutions, and can be extended to non-aqueous systems. The developed approach can be used to model processes in biological systems, as well as to extend related theoretical models further.

Motivation & Objective

• To improve the accuracy of solvation thermodynamics predictions using integral equation theories.
• To address the limitations of existing approximate integral equation methods in capturing solvation entropy and free energy.
• To develop a universal correction method applicable to both neutral and ionic solutes.
• To extend the model’s validity to non-ambient temperatures and non-aqueous solvents.
• To enable reliable modeling of solvation processes in biological and chemical systems.

Proposed method

• Extending a recently introduced pressure correction to systematically account for solvation entropy in integral equation theories.
• Rationalizing the pressure correction within the framework of solvation thermodynamics to improve physical consistency.
• Applying the corrected formalism to calculate solvation free energies using integral equation methods such as the reference interaction site model (RISM) or similar approaches.
• Validating the model against experimental data for a range of solutes in water at different temperatures.
• Testing the model’s transferability to ionic species and salt solutions.
• Extending the formalism to non-aqueous solvents to assess generality.

Experimental results

Research questions

• RQ1 Can a rationalized pressure correction significantly improve the prediction of solvation free energies in water across varying temperatures?
• RQ2 How accurately can the advanced pressure correction model predict solvation thermodynamics for both neutral and charged solutes?
• RQ3 To what extent is the model transferable to non-aqueous solvents and complex systems like salt solutions?
• RQ4 Does the inclusion of solvation entropy correction enhance the physical consistency and predictive power of integral equation theories?
• RQ5 Can the model be generalized to biological and chemical systems requiring accurate solvation thermodynamics?

Key findings

• The advanced pressure correction model accurately predicts solvation free energies in water at both ambient and non-ambient temperatures.
• The model successfully captures solvation thermodynamics for ionic solutes and salt solutions, demonstrating broad applicability.
• The approach is transferable to non-aqueous systems, indicating its universality across solvent types.
• The rationalization of the pressure correction within the solvation entropy framework improves the physical consistency of the model.
• The model enables reliable prediction of solvation thermodynamics in systems relevant to biological processes.
• The method provides a robust foundation for extending integral equation theories to complex solvation phenomena.