A century on from the discovery of superconductivity there is still a huge worldwide effort to understand the mechanism of this intriguing phenomenon and find new superconductors. Scientists recently discovered superconductivity in alkali metal iron selenium systems and explaining this observation is now of great interest.
UK researchers have taken a step in the right direction by reporting precise structural information for this family of superconductive materials. By understanding how vacancies in these structures’ compositions can be accommodated, the team hopes to have laid the foundation for all subsequent understanding of the origin of superconductivity in related systems.
Cation vacancy order in the K0.8+xFe1.6-ySe2 system: five-fold cell expansion accommodates 20% tetrahedral vacancies
J. Bacsa, A.Y. Ganin, Y. Takabayashi, K.E. Christensen, K. Prassides, M.J. Rosseinsky, J.B. Claridge, Chem. Sci., 2011, DOI: 10.1039/C1sc00070E