Abstract
The structural features of the superconducting Li3CsC60 fulleride are studied by synchrotron X-ray powder diffraction as a function of pressure and temperature. In contrast with the behavior of Li2CsC60, Li3CsC60 shows a phase transition below room temperature from fcc (space group Fm3̄m) to an orientationally ordered primitive cubic phase (space group Pa3̄), isostructural with the metastable phases of Na2A‘C60. Despite the slow cooling protocols adopted, the system shows no other phase transitions even after prolonged standing at 200 K. The pressure dependence of the structure of Li3CsC60 at ambient temperature was followed up to 8.12 GPa. A phase transition occurs at 0.72 GPa to a low symmetry fullerene bridged polymeric phase with short center-to-center interfullerene separations of ∼9.38 Å. This phase was found to be monoclinic (space group P21/a), isostructural with the low-temperature polymer phase of Na2RbC60 and the high-pressure polymer phase of Na2CsC60. The pressure evolution of the monoclinic lattice constants reveals a highly incompressible, tightly packed, and strongly anisotropic polymeric structure.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
