Electride: from computational characterization to theoretical design

Electrides are a class of materials in which anionic electrons are spatially separated from the positively charged crystalline framework. With such a unique structure, electrides show great potential in various applications, such as superconductivity, electronics, and catalysis. A number of organic and inorganic electrides have been successfully synthesized in experiment, and their novel electronic structures are studied both computationally and experimentally. Computational characterization can provide information which is difficult to be obtained from experiment. In electronic structure calculations, charge density, noncovalent interaction (NCI) index, electron localization function (ELF), and electrostatic potential (ESP) can be analyzed to identify anionic electrons in confined space. On the other hand, theoretical studies can also be used to design new electrides, such as in a recent instance of two‐dimensional (2D) electride screening. Alternatively, new applications and novel electron systems based on electrides can be explored theoretically. As an example, based on Ca2N electride, an intrinsic 2D electron gas system in free space (2DEG‐FS) has been proposed. With the aid of computational characterization and theoretical design, electride study will continue to be an important field in materials science. WIREs Comput Mol Sci 2016, 6:430–440. doi: 10.1002/wcms.1258 This article is categorized under: Structure and Mechanism > Computational Materials Science