气候变化领域集成服务门户(CCPortal): Liquid-Vapor Coexistence and Critical Point of Mg2SiO4 From Ab Initio Simulations

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DOI	10.1029/2020GL089599
	Liquid-Vapor Coexistence and Critical Point of Mg2SiO4 From Ab Initio Simulations
	Townsend J.P.; Shohet G.; Cochrane K.R.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:17
英文摘要	Hypervelocity impact-driven vaporization is characteristic of late-stage planet formation. Yet the behavior and properties of liquid-vapor mixtures of planetary materials of interest are typically unknown. Multiphase equations of state used in hydrodynamic simulations of planet impacts therefore lack reliable data for this important phenomenon. Here, we present the first constraints on the liquid-vapor critical point and coexistence phase boundary of Mg2SiO4 computed from ab initio molecular dynamics simulations. We found that the vapor is depleted in magnesium and enriched in silica and oxygen, while the coexisting liquid is enriched in magnesium and depleted in oxygen, from which we infer vaporization is incongruent. The critical point was estimated from an equation of state fit to the data. The results are in line with recent calculations of MgSiO3 and together confirm that extant multiphase equation of state (EOS) models used in planetary accretion modeling significantly underestimate the amount of supercritical material postimpact. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Binary mixtures; Calculations; Liquids; Magnesium; Magnesium compounds; Molecular dynamics; Oxygen; Silica; Silicon; Vaporization; Ab initio molecular dynamics simulation; Ab initio simulations; Coexistence phase; Hydrodynamic simulation; Hypervelocity impacts; Liquid-vapor critical points; Multiphase equation of state; Planetary materials; Equations of state; equation of state; hydrodynamics; magnesium; molecular analysis; oxygen; silicon; vaporization; water vapor
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/169783
作者单位	High Energy Density Physics Theory, Sandia National Laboratories, Albuquerque, NM, United States; Department of Aeronautics and Astronautics, Stanford University, Stanford, CA, United States
推荐引用方式 GB/T 7714	Townsend J.P.,Shohet G.,Cochrane K.R.. Liquid-Vapor Coexistence and Critical Point of Mg2SiO4 From Ab Initio Simulations[J],2020,47(17).
APA	Townsend J.P.,Shohet G.,&Cochrane K.R..(2020).Liquid-Vapor Coexistence and Critical Point of Mg2SiO4 From Ab Initio Simulations.Geophysical Research Letters,47(17).
MLA	Townsend J.P.,et al."Liquid-Vapor Coexistence and Critical Point of Mg2SiO4 From Ab Initio Simulations".Geophysical Research Letters 47.17(2020).