论文标题
金属和半法中红外振动光谱的第一原理理论：在石墨上的应用
First-principles theory of infrared vibrational spectroscopy in metals and semimetals: application to graphite
论文作者
论文摘要
我们开发了一种从头算法，以模拟金属系统在时间依赖性密度功能扰动理论框架中的红外振动响应。通过引入广义依赖频率的天生有效电荷张量，我们表明，金属反射率中的声子峰始终由Fano函数描述，Fano函数的形状由频率依赖性有效电荷和电子介电张量的复杂性确定。发现石墨的IR振动特性被选为代表性测试案例，以基于我们的方法进行基准测试。我们的方法为对金属的IR反射光谱的预测和理解提供了第一原则方案，当经历极高的压力条件时，可能代表了这些材料的少数可用研究工具之一。
We develop an ab initio method to simulate the infrared vibrational response of metallic systems in the framework of time-dependent density functional perturbation theory. By introducing a generalized frequency-dependent Born effective charge tensor, we show that phonon peaks in the reflectivity of metals can be always described by a Fano function, whose shape is determined by the complex nature of the frequency-dependent effective charges and electronic dielectric tensor. The IR vibrational properties of graphite, chosen as a representative test case to benchmark our method, are found to be accurately reproduced. Our approach offers a first-principle scheme for the prediction and understanding of IR reflectance spectra of metals, that may represent one of the few available tools of investigation of these materials when subjected to extremely high-pressure conditions.
