The content of the first chapter of the paper is highly related to the theme of the paper. However, the overall situation and some details of other people's work closely related to the content work are given in chapter 2 (that is, the basis of the follow-up work or another part of the comparative experiment). The first chapter and the second chapter are the relationship between the whole and the local details. If you don't write it, the second chapter has nothing to do with the first chapter, but the summary of the first chapter is biased.

The first chapter is the general principle of writing subordinate chapters: first, give the layout of key concepts, and then give other detailed research contents. On the one hand, the actual research contents of other researchers further illustrate the previous concept layout, on the other hand, the specific research examples of other researchers may have something special that needs to be pointed out.

For the layout of key concepts, a principle is:

Give a clear definition of common, important and in-depth research, and brush aside vague concepts. Not perfect, but exquisite. Especially in the field of chemistry, based on the fundamental theorem that "structure determines nature", specific structural characteristics must be clearly given, and things in structure and nature can be explained together.

The first chapter introduces the research background in an all-round way. Because the content of personal research only pays attention to one point, the process of moving perspective is from big to small. This is similar to peeling onions. The outside is the overall situation, and the inside is my own research content. At this time, the focus should be clear. Focus on your own research content, and those levels that are highly related to your own research content. Don't say anything irrelevant, or even say nothing.

There should be a natural transition between layers. When comparing different layers, give appropriate evaluation and explain the advantages of using this layer.

The summary part (Chapter 1) should give the background knowledge of the language described in the following chapters (Chapters 3 and 4) and construct the basic conceptual framework. Specifically, in the third and fourth chapters, key concepts should first appear in the first chapter and be explained in detail. In other words, the first chapter is to pave the way for follow-up.