Covalency of Valence Electrons in Liquid Silicon: A Direct X-ray Compton Scattering Measurement

我们用静电悬浮器测量了液态硅的康普顿分布，发现它与固态硅的康普顿分布基本相同。尽管它的金属性质，所获得的康普顿轮廓是很大程度上不同于具有相同的价电子密度的相互作用的自由电子气体。采用Car-Parrinello分子动力学模拟方法对液态硅的康普顿分布进行了分析，结果表明液态硅中存在共价键，这与第一性原理分子动力学模拟结果一致。

We have measured a Compton profile of liquid silicon with an electrostatic levitator and found that the Compton profile is much the same as that of solid silicon. Despite its metallic nature, the obtained Compton profile is largely different from that of an interacting free-electron gas with the same valence-electron density. Analysis of the Compton profile of liquid Si using Car-Parrinello Molecular Dynamics simulation shows the existence of covalent bonds in liquid silicon, which has been predicted by first-principles molecular dynamics simulation.