Intercalating Anions between Terminated Anion Layers: Unusual Ionic S-Se Bonds and Hole-Doping Induced Superconductivity in S_0.24(NH₃)_0.26Fe₂Se₂.

ABSTRACT: The pairing of ions of opposite charge is a central principle of chemistry. Even though the ability to intercalate anions is desirable for many applications, it remains a key challenge for numerous host materials with their outmost layers beingn anions. In this work, we introduce a hydrothermal ion-exchange synthesis to intercalate oxidative S and Se anions between the Se layers of FeSe, which leads to single crystals of novel compounds (Se/S)_x(NH₃)_yFe₂Se₂. In particular, the unusual anion-anion bonding between the intercalated S (or Se) and Se layers exhibits strong ionic characteristics. The charge transfer through the Se layer to S (or Se) intercalants is further confirmed by the elevated oxidation state of Fe ions and

SUBMITTER: Sun R 

PROVIDER: S-EPMC11132993 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature