[PDF] Computational Materials Science at Extreme Conditions

58800_7Tse,JohnS(UniversityofSaskatchewan)_ComputationalMaterialsScienceatExtremeConditions.pdf Computational Materials Science at Extreme Conditions

John S. Tse

Department of Physics and Engineering Physics

University of Saskatchewan

Saskatoon, Canada

Pressure is a thermodynamic parameter that can be varied conveniently in the laboratory by

10 orders of magnitude. It is a versatile tool for the manipulation of crystal structures and

the promotion of chemical reactions. Many novel phenomena have been identified under extreme temperature and pressure conditions. A recent example is the report of superconductivity in simple molecular hydrides with critical temperatures near room temperature! However, very often the characterization of high pressure samples is not an easy task. Moreover, the time-proven chemical principles under ambient conditions may not be extended to this situation. Theory and computation have become indispensable for the elucidation and prediction of many novel phenomena. In the last twenty years, there have been tremendous progress and breakthroughs in both high pressure instrumentation and development of efficient and accurate algorithms for accurate electronic structure calculations. In this presentation, topical issues such as the structural theory, chemical reactions, structure prediction and reaction transition path location based on First Principles electronic calculations will be illustrated, particularly with examples on how synergy between theory and experiment had led to new discoveries.