Low temperature microhardness of Xe-intercalated fullerite C₆₀

• Published in: Физика низких температур
• Date: 2005
• Main Authors: Fomenko, L.S., Lubenets, S.V., Natsik, V.D., Cassidy, D., Gadd, G.E., Moricca, S., Sundqvist, B.
• Format: Article
• Language: English
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2005
• Subjects: Низкотемпературная физика пластичности и прочности
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/121467
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Low temperature microhardness of Xe-intercalated fullerite C₆₀ / L.S. Fomenko, S.V. Lubenets1, V.D. Natsik, D. Cassidy, G.E. Gadd, S. Moricca, and B. Sundqvist // Физика низких температур. — 2005. — Т. 31, № 5. — С. 596-601. — Бібліогр.: 25 назв. — англ.

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).