Theses Doctoral

Atomistic simulations of minerals at extreme conditions

Luo, Chenxing

Understanding the Earth’s interior requires exploring minerals under extreme pressures and temperatures, conditions often unattainable by experimental methods. Atomistic simulations provide a powerful tool to investigate these extreme environments, offering insights into minerals' physical and chemical behavior deep within the Earth. However, complex phase relations and pronounced anharmonic effects pose significant challenges to these simulations.

To address these challenges, we developed advanced methodologies and employed cutting-edge atomistic simulation techniques. Our work focused on modeling phonon behavior, simulating X-ray, IR, and Raman spectroscopy, and evaluating key properties such as thermodynamics, compressive strength, and thermoelasticity. We extended the quasiharmonic approximation for thermoelasticity and introduced a new formalism for third-order elasticity to tackle the complexities inherent in these systems. Our research sheds light on phenomena like hydrogen bond disordering, tunneling, diffusion, and hydrogen bond-induced elastic anisotropy under extreme pressure. These advancements significantly enhance our understanding of the thermal and chemical structures of the Earth’s deep interior.

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More About This Work

Academic Units
Materials Science and Engineering
Thesis Advisors
Wentzcovitch, Renata Maria Mattosinho
Degree
Ph.D., Columbia University
Published Here
October 16, 2024