论文标题
铁的高压熔化特性的有效分析方法
Efficient Analytical Approach for High-Pressure Melting Properties of Iron
论文作者
论文摘要
铁代表地球核心的主要成分，但其高压熔图图仍然模棱两可。在这里，我们提出了一种简单的分析方法，以预测深地球条件下铁的熔融特性。在我们的模型中，固相的非谐自由能由量子统计力学中的力矩扩展技术直接确定。与Lindemann标准相关的振动不稳定性相关的基础可以推断熔化温度。此外，我们将热膨胀过程与剪切响应相关联，以解释熔化时原子体积，焓和熵的不连续性。我们的数值计算与最近的实验和模拟一致。获得的结果将改善对地球结构，动力学和进化的理解。
Iron represents the principal constituent of the Earth's core, but its high-pressure melting diagram remains ambiguous. Here we present a simple analytical approach to predict the melting properties of iron under deep-Earth conditions. In our model, anharmonic free energies of the solid phase are directly determined by the moment expansion technique in quantum statistical mechanics. This basis associated with the Lindemann criterion for a vibrational instability can deduce the melting temperature. Moreover, we correlate the thermal expansion process with the shear response to explain a discontinuity of atomic volume, enthalpy, and entropy upon melting. Our numerical calculations are quantitatively consistent with recent experiments and simulations. The obtained results would improve understanding of the Earth's structure, dynamics, and evolution.
