论文标题
X射线光谱中的真实空间绿色的功能方法
Real-space Green's function approach for intrinsic losses in x-ray spectra
论文作者
论文摘要
X射线光谱中的固有非弹性损失源自相互作用的电子系统中的激发，这是由于突然产生的核心孔。这些损失表征了在X射线光发射光谱（XPS）中观察到的特征，在这里，我们提出了一个互补的{\ it i ab intio}真实空间Green的函数（RSGF）langreth累积的概括，以动态筛选的核心 - 核 - 孔相互作用$ W_C（ω）$和独立的粒子响应功能。我们发现，累积的内核$β（ω）$类似于XAS，但用单极选择规则代替了过渡操作员，而过渡算子则代替了核心孔电位。该行为反映了损耗函数的分析结构，峰值在介电函数的零附近，与DELEACALIZED的准玻色刺激一致。当$ w_c（ω）$是本地化并在球面对称时，该方法会简化。对电子气体，钠和一些早期过渡金属化合物进行了说明性结果和比较。
Intrinsic inelastic losses in x-ray spectra originate from excitations in an interacting electron system due to a suddenly created core-hole. These losses characterize the features observed in x-ray photoemission spectra (XPS), as well Here we present a complementary {\it ab initio} real-space Green's function (RSGF) generalization of the Langreth cumulant in terms of the dynamically screened core-hole interaction $W_c(ω)$ and the independent particle response function. We find that the cumulant kernel $β(ω)$ is analogous to XAS, but with the transition operator replaced by the core-hole potential with monopole selection rules. The behavior reflects the analytic structure of the loss function, with peaks near the zeros of the dielectric function, consistent with delocalized quasi-boson excitations. The approach simplifies when $W_c(ω)$ is localized and spherically symmetric. Illustrative results and comparisons are presented for the electron gas, sodium, and some early transition metal compounds.
