Low temperature thermal expansion of fullerite C60 alloyed with argon and neon

Анотація

The linear thermal expansion of compacted fullerite C₆₀ alloyed with argon (Ar_xC₆₀) and neon (Ne_xC₆₀) are investigated by a dilatometric method. The experimental temperature is 2-12 K. In the same temperature interval the thermal expansion of Ar_xC₆₀ and Ne_xC₆₀ are examined after partial desaturation of the gases from fullerite. It is found that Ar and Ne alloying affects the temperature dependence of the thermal expansion coefficient of C₆₀ quite appreciably. The libration and translation contributions to the thermal expansion of pure C₆₀ are separated. The experimental results on the thermal expansion are used to obtain the Debye temperature of pure C₆₀. The effects observed are tentatively interpreted.