Molecular Dynamics Simulations of Solutes in Liquid Water and at the Ice/Water Interface

           

Principal Investigator

A. D. J. Haymet

School of Chemistry

University of Sydney

Solutes have a huge impact on the thermodynamic properties of both solid and liquid water. These solutes have important biological and technological applications. In this project we will perform molecular dynamics (MD) on model systems including inert gases in water, electrolytes in water and model 'antifreeze' proteins at the ice/water interface. We will calculate static properties such as the pair correlation functions and thermodynamic properties such as entropy, free energy and the potential of mean force.

In this project we will perform molecular dynamics (MD) on model systems including inert gases in water, electrolytes in water and model 'antifreeze' proteins at the ice/water interface. We will calculate static properties such as the pair correlation functions and thermodynamic properties such as entropy, free energy and the potential of mean force.

 

Co-Investigators

   

J. W. Arthur

School of Chemistry

University of Sydney

   

Projects

g59 -VPP

   
         
           

 

What are the results to date and the future of the work?

Extensive modification of the original molecular dynamics (MD) code has been undertaken. These changes include the incorporation of the ability to simulate in flexible cell sizes and shapes in both NVE and NPT ensembles, inclusion of the pressure tensor and ability to simulate water with fully charged solute particles. Much time has been spent testing and debugging the new version of the code. Simulations have been performed to generate two different ice/water interfaces and extensive work has been carried out in order to equilibrate these ice/water interfaces.

What computational techniques are used?

Our simulations solve first order differential equations (Hamilton's equations of motion) using a fifth value Gear Predictor Corrector algorithm. Long range charge-charge interactions are handled using the Ewald summation technique.