Structure and electronic transport properties of metallic liquids at conditions of planetary cores

在行星内部通过磁流体动力学对流产生磁场的模型中，电导率是一个关键参数。液态金属的这一关键材料参数的测量是不可能的日期通过实验在相关条件下，和发电机模型依赖于外推从低压/温度实验，或最近的从头计算结合分子动力学和线性响应计算，使用Kubo-Greenwood公式的传输系数。这样的计算已经进行了铁，铁合金，H，He和H-He的混合物，以覆盖内部的类地和巨大的气体行星。这些模拟计算是昂贵的，一个有效的准确的计划来确定电导率是可取的。在这里，我们提出了一个模型，可以在更低的计算成本，提供这些信息。它基于Ziman电导率理论，该理论使用液体结构的信息，结合电子-电子，电子-原子和原子-原子相互作用的内部一致的电势模型。在建议中，我们制定的理论，并将其扩展到多组分系统。我们指出，拟合的液体结构因子是在这个过程中的关键组成部分，并设计策略，如何可以有效地做到这一点。以一种化学上一致的方式拟合结构因子，并具有一个可转移的电子-原子势，我们就可以相对便宜地预测各种条件下的电导率。只有有限的分子动力学模拟，以获得结构factors.In拟议的项目中，我们将测试和推进这个模型的液体铝，自由电子类金属，我们已经研究了与Kubo-Greenwood方法之前。然后，我们将能够预测的Fe，Fe轻元素和H，He，以及H-He系统的导电性，分别与类地行星和巨型气体行星的行星内部。

Electrical conductivity is a key parameter in models of magnetic field generation in planetary interiors through magneto-hydrodynamic convection. Measurements of this key material parameter of liquid metals is not possible to date by experiments at relevant conditions, and dynamo models rely on extrapolations from low pressure/temperature experiments, or more recently on ab-initio calculations combining molecular dynamics and linear response calculations, using the Kubo-Greenwood formulation of transport coefficients. Such calculations have been performed for Fe, Fe-alloys, H, He and H-He mixtures to cover the interior of terrestrial and giant gas planets. These simulations are computationally expensive, and an efficient accurate scheme to determine electrical conductivities is desirable.Here we propose a model that can, at much lower computational costs, provide this information. It is based on Ziman theory of electrical conductivity that uses information on the liquid structure, combined with an internally consistent model of potentials for the electron-electron, electron-atom, and atom-atom interactions. In the proposal we formulate the theory and expand it to multi-component systems. We point out that fitting the liquid structure factor is the critical component in the process, and devise strategies on how this can be done efficiently. Fitting the structure factor in a thermodynamically consistent way and having a transferable electron-atom potential we can then relatively cheaply predict the electrical conductivity for a wide range of conditions. Only limited molecular dynamics simulations to obtain the structure factors are required.In the proposed project we will test and advance this model for liquid aluminum, a free-electron like metal, that we have studied with the Kubo-Greenwood method previously. We will then be able to predict the conductivities of Fe, Fe-light elements and H, He, as well as the H-He system that are relevant to the planetary interiors of terrestrial and giant gas planets, respectively.