CAREER: Understanding the thermodynamics of crystalline materials using advanced molecular simulation sampling methods

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

1351635 Shirts The theory of solid phase materials has focused to a large extent on zero temperature crystal minima and harmonic approximations around these minima. In realistic systems, such as crystals of pharmaceutical agents or metal oxides for functional materials, the room temperature or high temperature properties are of most interest. This means free energy minima and thermodynamic ensembles are the important quantities, rather than potential energy minima and fixed structures. Little previous research has examined the free energy landscape of solids more complex than Lennard-Jones spheres or atomic salts. This proposal brings together methods for simulating multiple thermodynamic ensembles in new ways in order to achieve the necessary levels of sampling required for realistic crystal systems. The proposed methods will scale in a straightforward way to multicomponent crystals and to potential functions of increasing accuracy. A better understanding of the thermodynamics of molecular crystals and an improved ability to quantitatively predict their properties is vital for continued improvement of the pharmaceutical development pipeline, allowing drugs to be formulated and processed more safely, easily and cheaply. The methods developed here will also be useful for predictive tools for processing of a broad range of crystalline materials including pigments, pesticides and other agrochemicals, food additives, electronic materials, ceramics and explosives.