Interstitial electrons
Their position away from atomic nuclei makes interstitial electrons especially sensitive to crystal geometry, pressure, dimensionality and local distortions. They can be localized as quasi-atomic states or form extended bands.
About electrides
Electrides are materials in which electrons can act as anions.
In an electride, some valence electrons are spatially separated from atomic sites and occupy cavities, channels or interlayer regions of a crystal. These interstitial states can form an electronic subsystem with its own bandwidth, filling, interactions and response to external conditions.
Related terms
Electrenes are ultrathin, low-dimensional forms derived from electrides. The terms magnetrides and magnetrenes describe cases where interstitial electronic states develop magnetic order. They are treated here as related phenomena within the broader physics of electrides.
What theory resolves
Ab initio calculations connect crystal structure with electronic states. Localized Wannier functions, screened interactions and many-body techniques then allow the interstitial subsystem to be analysed beyond a simple band picture.
Scientific claims on this site are drawn from the listed publications and the official RSF project record. Predictions, computed results and experimentally established observations are distinguished in the relevant context.