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DFT/Density Functional Theory Modeling Mathematical Analysis.md

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 TODO: 关于加入更多自由度来更好地拟合交换关联泛函的问题，用到了再看吧。
 
 
+接下来要解决的问题：
+* 如何近似表示交换关联能？
+* 程序实现上，通常来说是怎样做的？

SiC/Springer Handbook of Surface Science.md

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+# Springer Handbook of Surface Science
+
+## 5. Ab Initio Simulations of Semiconductor and Interfaces
+
+### Abstract
+
+本文不会介绍很多的方法，而会通篇只介绍一种方法，会使用这一种方法来计算各种与表面和界面有关的实际问题。
+
+### 5.1 Overview
+
+Furthermore, implementations of hybrid functionals or Hubbard corrections
+  allow us to study the effects of a strongly correlated electron gas,
+  which are difficult to describe in the pure, in principle exact, DFT formulation,
+  based on a nearly homogeneous electron-gas treatment of the electron density,
+  without severe trade-offs in computational cost.
+
+### 5.2 Theoretical Framework
+