Low temperature microhardness of Xe-intercalated fullerite C₆₀

Autor: Fomenko, L.S., Lubenets, S.V., Natsik, V.D., Cassidy, D., Gadd, G.E., Moricca, S., Sundqvist, B.
Jazyk: angličtina
Rok vydání: 2005
Předmět:
Popis: The Vickers microhardness of Xe-intercalated polycrystalline fullerite C₆₀ (XexC₆₀, x ≃ 0.35) is measured in a moderately low temperature range of 77 to 300 K. A high increase in the microhardness of the material (by a factor of 2 to 3) as compared to that of pure C₆₀ single crystals is observed. It is shown that the step-like anomaly in the temperature dependences of the microhardness of pure C₆₀ single crystals recorded under the orientational fcc-sc phase transition (Tc ≃ 260 K) is also qualitatively retained for XexC₆₀, but its onset is shifted by 40 K towards lower temperatures and the step becomes less distinct and more smeared. This behavior of ̅NV(T) correlates with x-ray diffraction data, the analysis of which revealed a considerable influence of xenon interstitial atoms on the peculiar features of fullerite thermal expansion due to orientational phase transitions (see the paper by A.I. Prokhvatilov et al. in this issue).
Databáze: OpenAIRE