论文标题
液体水的X射线吸收光谱中的同位素效应
Isotope effects in x-ray absorption spectra of liquid water
论文作者
论文摘要
通过电子孔激发理论中的多体方法研究了液体水的X射线吸收光谱中的同位素效应。光和重水的分子结构都是基于先进的深度学习技术来建模的。通过扫描密度功能理论获得的从头算数据进行了神经网络的培训。实验观察到的在X射线吸收光谱中的同位素效应在理论上是半定量的。与正常水中的光谱相比，重水中的蓝光且明显的前边缘和主要边缘反映出，重水在氢键网络的短和中间范围内更加结构。相比之下，在边缘的频谱上，同位素对光谱的效应可以忽略不计，这与衍射实验中观察到的两种液体中相同的长距离顺序是一致的。
The isotope effects in x-ray absorption spectra of liquid water are studied by a many-body approach within electron-hole excitation theory. The molecular structures of both light and heavy water are modeled by path-integral molecular dynamics based on the advanced deep-learning technique. The neural network is trained on ab initio data obtained with SCAN density functional theory. The experimentally observed isotope effect in x-ray absorption spectra is reproduced semiquantitatively in theory. Compared to the spectrum in normal water, the blueshifted and less pronounced pre- and main-edge in heavy water reflect that the heavy water is more structured at short- and intermediate-range of the hydrogen-bond network. In contrast, the isotope effect on the spectrum is negligible at post-edge, which is consistent with the identical long-range ordering in both liquids as observed in the diffraction experiment.
