Probing Iron in Earth's Core With Molecular-Spin Dynamics

Svetoslav Nikolov; Kushal Ramakrishna; Andrew Rohskopf; Mani Lokamani; Julien Tranchida; John Carpenter; Attila Cangi; Mitchell A. Wood

arXiv · 2311.08737

Probing Iron in Earth's Core With Molecular-Spin Dynamics

Svetoslav Nikolov·Kushal Ramakrishna·Andrew Rohskopf·Mani Lokamani·Julien Tranchida·John Carpenter·Attila Cangi·Mitchell A. Wood

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Abstract

Dynamic compression of iron to Earth-core conditions is one of the few ways to gather important elastic and transport properties needed to uncover key mechanisms surrounding the geodynamo effect. Herein a new machine-learned ab-initio derived molecular-spin dynamics (MSD) methodology with explicit treatment for longitudinal spin-fluctuations is utilized to probe the dynamic phase-diagram of iron. This framework uniquely enables an accurate resolution of the phase-transition kinetics and Earth-core elastic properties, as highlighted by compressional wave velocity and adiabatic bulk moduli measurements. In addition, a unique coupling of MSD with time-dependent density functional theory enables gauging electronic transport properties, critically important for resolving geodynamo dynamics.

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Svetoslav Nikolov, Kushal Ramakrishna, Andrew Rohskopf, Mani Lokamani, Julien Tranchida, John Carpenter, Attila Cangi, Mitchell A. Wood. 2023-11-15. Probing Iron in Earth's Core With Molecular-Spin Dynamics. https://arxiv.org/abs/2311.08737

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