Abstract:

Charge density difference (CDD) can investigate the charge redistribution of molecules, clusters and solid materials, as well as the interaction between molecules and solid materials, which has been widely used in electronic structure analysis. Based on the authors' theoretical research and teaching practice of "application of density functional theory in chemistry research", the authors found that the calculation methods and results of charge density difference vary along with the different research objectives. According to the research objectives, the charge density difference can be divided into atom-based, fragment-based, specific object-based and spin density. If one can't understand the concept correctly and establish a reasonable model, it is hard to get the correct electronic structure information. In the present work, authors systematically sort out the types, calculation methods and applicable research system of CDD calculation. Base on the teacher's explanation and demonstration, students' practice, as well as exploratory homework, students can understand and master the electronic analysis method of charge density difference, which provides important support for teaching and scientific research.

Key words: Charge density difference, Electronic structure, Density functional theory, Spin density