Thermal and Electrical Conductivity of Iron at Planetary Core Conditions from Ab Initio Computations

铁在高压和高温下的导热性和导电性是确定地球行星核心磁场生成特征和热历史的关键约束。然而，由于在高压下测量这些特性的巨大技术挑战，它们的值仍然非常不确定，变化约为三倍。作为一个例子，这种差异足以导致地球核心的显着不同的热历史，这决定了其磁场的发展和产生。我们将准确可靠地计算fcc，bcc，hcp和液态铁的热导率和电导率，在与地球核心相关的压力和温度范围内（0-400 GPa; 1000-7000 K）。为此，我们将在密度泛函理论（DFT）的框架内使用最先进的电子结构方法，以独立地获得晶格热导率，电子热导率和电导率。这也将使我们能够在高压和高温下自洽地测试理论近似值，目前在非常高的压力下对电导率和热导率的估计是基于这些理论近似值。

The thermal and electrical conductivities of iron at high pressure and temperature are key constraints in determining the character of magnetic field generation in, and thermal history of, terrestrial planetary cores. Yet, as a result of tremendous technical challenges associated with the measurement of these properties at high pressure, their values remain very uncertain, varying by about a factor of three. As an example, this difference is sufficient to result in notably different thermal histories for the Earth s core, which crucially determines the development and generation of its magnetic field. We will accurately and reliably compute the thermal and electrical conductivity of the fcc, bcc, hcp, and liquid iron, over the range of pressures and temperatures relevant to terrestrial cores (0-400 GPa; 1000-7000 K). To do this we will use state of the art electronic structure methods in the framework of density-functional theory (DFT), to independently obtain the lattice thermal conductivity, electronic thermal conductivity and electrical conductivity. This will also enable us to self-consistently test, at high pressure and temperature, the theoretical approximations upon which current estimates of electrical and thermal conductivity at very high pressures are based.