Electronic Correlation Strength of Inorganic Electrides from First Principles

Abstract

Strongly correlated electron systems, generally recognized as d- and f-electron systems, have attracted attention as a platform for the emergence of exotic properties such as high-Tc superconductivity. However, correlated electron behaviors have been recently observed in a group of novel materials, electrides, in which s-electrons are confined in subnanometer-sized spaces. Here, we present a trend of electronic correlation of electrides by evaluating the electronic correlation strength obtained from model parameters characterizing effective Hamiltonians of 19 electrides from first principles. The calculated strengths vary in the order 0D ≫ 1D > 2D ∼ 3D electrides, which corresponds to experimental trends, and exceed 10 (a measure for the emergence of exotic properties) in all of the 0D and some of the 1D electrides. We also found the electronic correlation depends on the cation species surrounding the s-electrons. The results indicate that low-dimensional electrides will be new research targets for studies of strongly correlated electron systems.

Localization Mechanism of Interstitial Electronic States in Electride Mayenite

“…The results obtained in this work clearly demonstrate the tendency toward the formation of electride diamagnetic pairs in C12A7: e – with electron anions coupled antiferromagnetically with each other ( S = 0), which, in particular, may be in favor of the bipolaronic mechanism of superconductivity in mayenite. The localization of electride states in mayenite, together with the data obtained earlier − for other electrides, allows us to suggest the importance of taking into account many-particle correlation effects when considering the electride subsystem.…”

Multi-dimensional inorganic electrides for energy conversion and storage

“…Compared with these low-dimensional electrides, the formation conditions of high-dimensional electrides are more complex, resulting in a sharp decrease of electrides with the increase of dimensions (0D / 3D). Besides, Hideo's team 72 claimed that low-dimensional electrides would become new targets for the study of strongly correlated electronic systems (strongly correlated strength: 0D [ 1D > 2D-3D). Fortunately, based on recently identied electrides, 14,35,43,[50][51][52][53] one can nd that inorganic electrides are mainly concentrated in 0D and 1D systems.…”

Electronic correlations and intrinsic magnetism of interstitial quasi-atomic states in Li8Au electride

“…14,15 As shown earlier, predictions based on density functional theory (DFT) level are not always able to fully reflect the physics of the electride subsystem since many-body effects need to be taken into account. [16][17][18][19][20][21][22][23][24] Usually, electron correlation effects enrich the physics of the phenomena that occur in materials and dramatically improve their functionality, and electrides are not an exception to this rule. It has been recently discovered that some electrides may possess a specific type of intrinsic magnetism unrelated to the electronic subsystem of atoms.…”