The formation of the Na2CsC60 superconducting phase is studied precisely; this is the first face-centered cubic (fcc) M3C60-series superconductor showing lattice contraction. Various nominal compositions of NaxCsyC60 (x+y=3) always give rise to one single superconducting Na2CsC60 crystal phase (superconducting transition temperature of 12 K) with preferential site selections of the two alkali metals, Cs in the larger octahedral and Na in the smaller tetrahedral sites. The obtained superconducting fractions are described on the basis of the supposed stoichiometric fcc M3C60 formation.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry