What is it about?
Ni is the second most abundant element in the Earth's core. However, its effects on the inner core structure and formation process are usually disregarded because its electronic structure and size are similar to those of Fe. Our present work challenges this generally accepted assumption. We have shown for the first time that Ni can significantly affect the stable crystalline phase and the formation of solid Fe alloys in the Earth’s inner core. This is unexpected in light of previous studies of core structure and formation.
Featured Image
Photo by USGS on Unsplash
Why is it important?
This work demonstrates that the core's second most abundant element, Ni, strongly affects Fe's crystallization process. Ni can stabilize the bcc phase and accelerate Fe's crystallization under core pressures. The simulation results suggest that alloying Fe with Ni can promote the coexistence of the bcc and hcp phases in the solid inner core. This is critical in understanding the inner core's nucleation and the origin of its complex solid structure.
Perspectives
I hope this article provides a more realistic basis for understanding the state and formation of Earth's inner core. It may inspire research into the properties of Fe-Ni alloys under conditions of other planetary cores, advancing the understanding of the habitability of terrestrial planets.
Renata Wentzcovitch
Columbia University
Read the Original
This page is a summary of: Unveiling the effect of Ni on the formation and structure of Earth’s inner core, Proceedings of the National Academy of Sciences, January 2024, Proceedings of the National Academy of Sciences,
DOI: 10.1073/pnas.2316477121.
You can read the full text:
Contributors
The following have contributed to this page
