Reversible pressure-driven nanoscale phase separation in Rb4C60
2009 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 79, no 8, 081403- p.Article in journal (Refereed) Published
Wepresent Raman spectra for Rb4C60 at pressures up to 13GPa. Above 1 GPa we observe a phase separation ofRb4C60 into Rb6C60 and Rb3C60, identified by a splitting ofthe Ag(2) mode and the appearance of characteristic Raman modesof the daughter phases. Remarkably, the phase separation is completelyreversible and the sample returns to a homogeneous Rb4C60 phaseafter pressure release. The reversibility of the phase separation suggeststhat the structural change is associated with small displacements ofRb ions in the unit cell, giving local differences inthe charge state of the C60 molecules. The pressure dependenceof the Raman shifts agrees well with earlier measurements. Ourobservation of a reversible phase separation explains several peculiar resultsreported earlier for Rb4C60.
Place, publisher, year, edition, pages
American Physical Society , 2009. Vol. 79, no 8, 081403- p.
Fullerenes, C60, fullerides, fullerene compounds, Rb4C60, high-pressure effects, phase separation, Raman spectra, Raman spectroscopy, rubidium compounds, Rb6C60
Condensed Matter Physics
Research subject Physics
IdentifiersURN: urn:nbn:se:umu:diva-18515DOI: 10.1103/PhysRevB.79.081403OAI: oai:DiVA.org:umu-18515DiVA: diva2:160150
Rapid Communication2009-02-122009-02-122015-09-28Bibliographically approved